UltraTone™ Core Master Abs & Waist Sculptor
Want a tighter, more toned core without living at the gym? Wish you could train your abs discreetly under your clothes? That's what this is for.
SCULPT YOUR CORE. COMFORT YOUR LOWER BACK.
Dedicated side-ab electrodes activate your obliques for a more defined waist; turn the belt around for soothing, massage-like lower-back activation.
PATENTED TECHNOLOGY • AS SEEN ON TV • SHIPS FROM BEVERLY HILLS • FREE SHIPPING
SHOP NOW, PAY LATER — interest-free installment options available at checkout.
NOT A REGULAR WAIST TRAINER.
SLIM, LIGHTWEIGHT CORE ACTIVATION WITH MORE CONTROL.
UltraTone™ offers 10 modes and 30 intensity levels in an adjustable unisex belt. Its low-profile design wears discreetly under clothing for targeted core activation anywhere.
What UltraTone™ Does for You
- The most advanced GYM IN A BOX® core belt — 10 modes and 30 intensity levels for precise control.
- One-size, slim and lightweight — wears discreetly under clothing.
- Targeted StimFit activation for abs, obliques and core.
- Dedicated side-ab/waist electrode pads stimulate your obliques to help tone your abs & waist.
- Turn it around for a soothing, massage-like activation across your lower back.
- Wireless and rechargeable — no wires, no gel pads.
- Honest expectations: feel activation from your first 15-minute session; visible changes build with consistent daily use. Individual results vary.
- FREE shipping on eligible U.S. orders.
Next-Generation Core Activation.
Wear it. Press start. Train your core in 15 minutes.
UltraTone™ Core Master Abs & Waist Sculptor is the premium GYM IN A BOX® core belt. Patented ToneUp15® StimFit technology delivers targeted muscle activation to your abs, obliques and core through an adjustable, one-size belt designed for discreet wear.
How It Works — In Plain Words
This premium belt wraps your waist with contact pads. Patented microcurrent signals make your abs and obliques contract on their own — like doing hundreds of crunches while you relax. With 10 programs and 30 intensity levels, you control the pattern and strength. Its slim, one-size design sits discreetly under clothing, and you can even turn it around for a soothing, massage-like activation across your lower back. With consistent daily use in 15-minute sessions, these contractions help tone and strengthen your core. Individual results vary.
Why Choose UltraTone™?
- Most advanced core belt in the GYM IN A BOX® lineup
- 10 modes and 30 intensity levels — more programs and finer control than standard belts
- One-size adjustable fit — no size selection needed
- Slim, lightweight, low-profile design for discreet wear
- Lower-back option: reverse the belt for a soothing activation
How This Technology Helps You
- Where it works: Abs, obliques, lower back and core.
- What it does: Patented ToneUp15® StimFit pulses activate core muscles through adjustable programs.
- What that means for you: You can add hands-free core activation to your routine — at home, at work or on the go.
Simple routine: Wrap the belt snugly around your waist, choose a comfortable program and intensity, then complete the automatic 15-minute session.
Specifications
- 10 stimulation modes
- 30 adjustable intensity levels
- One-size, adjustable unisex fit
- Slim, lightweight and low-profile design
- Wireless and USB rechargeable
- Automatic 15-minute sessions
- No wires, no gel pads
All GYM IN A BOX® belts are powered by patented microcurrent StimFit technology — 100% wireless, 15-minute sessions, no gym required.
WHICH ONE IS FOR ME?
- MagicTone™ – tones and tightens your abdominal muscles and helps reduce waist size — straightforward abs & core activation, plus sauna-effect sweat and posture support in a corset design.
- UltraTone™ Core Master Abs & Waist Sculptor – targeted abs and oblique activation in a slim belt that can be worn under clothing for work, travel or daily routines. Reposition it for massage-like lower-back activation.
- SlimCore™ – tones and tightens abs while you sweat — the warming option with heating warmth and a skin-rejuvenation function.
- ThermaLuxe™ Smart Beauty Sculpt Belt – firms, tones and sculpts the waistline — the luxury beauty-and-wellness edition with cutting-edge design: heat, vibration, light and microcurrent.
- STIMFITBELT™ | MEN'S ULTIMATE ABS BUILDER – the men’s fit: tones and tightens abdominal muscles and reduces waist size, with sauna-effect sweat and posture support.
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5-in-1 Full Body ULTRA Muscle Booster Kit – tones and activates your full body in 15 minutes: core, arms, thighs and calves — the complete wireless system with 5 pieces for total-body muscle activation.
How to Use
- Charge the controller fully before first use.
- Lightly mist the contact pads and your skin with water.
- Wrap the belt snugly around your waist.
- Power on, choose a program, then increase intensity gradually.
- Complete the automatic 15-minute session.
Care
Wipe pads gently after use. Do not immerse in water.
SAFETY
Adult use only. Not for use during pregnancy. Do not use with a pacemaker or implanted electronic device.
CONSULT YOUR DOCTOR: If you have a medical condition, pacemaker, implanted device, are pregnant, or have any concerns, consult your doctor before use.
GYM IN A BOX® consumer fitness devices are intended for fitness and wellness use and are not intended to diagnose, treat, cure, or prevent any disease or medical condition. Individual experiences and results may vary.
During weight-loss journeys—including for adults using GLP-1 medications—maintaining muscle-focused movement, resistance training, and adequate nutrition remains important. This wearable can support muscle engagement as part of that broader routine; it is not intended to prevent or treat muscle loss.
State-of-the-Art Muscle Technology—Designed for Real Life
GYM IN A BOX® brings professional-inspired muscle-activation technology into a wearable belt you can use at home or on the go—without the recurring appointments, travel time, and cumulative expense of studio-based sessions.
Add to cart — train your core in 15 minutes today.
PATENTED TECHNOLOGY • CREATED BY CRISTIANI'S BALANCE FITNESS & NUTRITION, LLC
Our proprietary wearable technology is protected by U.S. patents, including U.S. Utility Patent No. 11,925,799 B2 and U.S. Design Patent No. D846,836 S.
GYM IN A BOX® USA | ToneUp15® StimFit Technology
Designed and developed in the USA • Established 2015.
Patented wearable fitness, beauty and recovery technology—designed for powerful routines that fit real life.
GYM IN A BOX® combines portable design with ToneUp15® Pulse Body StimFit Technology to support targeted muscle activation and convenient self-care at home, at work or while traveling.
Choosing Your GYM IN A BOX®
What is GYM IN A BOX®?
GYM IN A BOX® is a Beverly Hills–based wearable fitness and beauty technology brand founded in 2015. Our portable systems are designed to support muscle activation, toning, performance, beauty and recovery without requiring a traditional gym setup.
What is ToneUp15® Pulse Body StimFit Technology?
ToneUp15® Pulse Body StimFit Technology uses controlled electrical stimulation to create muscle contractions in the targeted area. Intensity is adjustable, so you can begin low and increase gradually according to the instructions supplied with your product.
Which product should I choose?
- Abs, waist and core: Choose one of our StimFitBelts™.
- Multiple body areas: The 5‑in‑1 Full Body Muscle Booster Performance System™ targets the abs, arms, legs, calves and glutes.
- Wearable apparel: BODYSCULPT™ Pants, GluteMaster Shorts, the BodyTone StimFit™ PowerShirt and BodyTone PRO™ PowerSuit provide integrated activation zones.
- Beauty and self-care: Explore FACETONE™, LUMILUXE™, iGLOW™ and ULTRAFIRM™.
- Recovery: Explore VitalStep™ and our sports-therapy systems.
Each product page lists its target areas, modes, intensity levels, sizing and session time.
Are the products unisex?
Yes. Our fitness wearables are designed for adult women and men. Apparel and belt sizing varies by product, so always use the size chart on the individual product page.
How do I choose my size?
Our apparel generally runs true to size. Measure yourself and compare your measurements with the size chart on the product page. Do not choose a smaller size merely for extra compression; the activation zones must sit correctly against the body.
Using Your Device
How long is a session?
Many ToneUp15® routines are designed for approximately 15 minutes. Some products have different programmed session times, including BODYSCULPT™ Pants. Follow the instructions provided with your specific device and do not exceed the recommended use.
How often can I use it?
Follow the schedule in your product instructions. Start conservatively, allow your body to adapt and avoid repeatedly stimulating the same muscle group beyond the recommended session time.
Does GYM IN A BOX® replace exercise?
It is designed to complement an active lifestyle and make targeted muscle activation more convenient. It is not a substitute for all movement, resistance training, balanced nutrition or medical care.
Is it intended for weight loss?
No. Our StimFit devices are not intended to produce weight loss. They are designed for fitness, muscle activation, toning and wellness support. Healthy body-composition goals still require appropriate nutrition, movement and lifestyle habits.
Is the sensation a vibration?
The tingling or pulsing sensation comes from electrical stimulation and the resulting muscle contractions. It is not simply mechanical vibration. Begin at the lowest intensity and increase gradually only when the device is positioned correctly and feels comfortable.
Why do the contractions feel weaker than before?
First check the charge level, controller connection, placement and skin contact. For products that require conductive contact, lightly moisten the appropriate contact area with water as directed—never use oils or lotions beneath the activation pads. Increase intensity gradually within your comfort level. If the issue continues, contact customer support with a short video or photo of the setup.
Why does the device not pulse when it is off my body?
Many of our systems include load detection and will not activate properly unless the contact areas are positioned fully against the skin. This is a safety feature, not a defect.
How long should I charge the controller?
Unless your product instructions state otherwise, allow approximately 90 minutes for a full charge before first use. Use the supplied charging accessories and keep controllers away from water.
Can I wear it while working, relaxing or traveling?
Many customers use our wireless wearables while working from home, relaxing or traveling. Use the device only where you can remain aware of the sensation and stop safely. Do not use it while driving, sleeping, bathing or performing any activity where involuntary muscle contractions could create risk.
Safety and Care
Who should not use electrical-stimulation products without medical clearance?
Do not use during pregnancy. Do not use if you have a pacemaker, defibrillator or another implanted electronic device. Ask a licensed healthcare professional before use if you have metal implants, recent surgery or injury, epilepsy, heart disease, cancer, diabetes, impaired sensation, a serious medical condition, or any concern about whether electrical stimulation is appropriate for you.
Where should I not place the device?
Use only on the body areas specified in the product instructions. Do not place stimulation across the chest, on the front or sides of the neck, on the head, over broken or irritated skin, or on areas with reduced sensation. Stop immediately if you experience pain, burning, dizziness, skin irritation or unusual discomfort.
Are these medical devices?
GYM IN A BOX® products are consumer fitness, beauty and wellness products. They are not intended to diagnose, treat, cure or prevent any disease or medical condition. Results vary.
How do I clean wearable apparel and belts?
Remove all controllers and electronic components before cleaning. Hand wash only when permitted by the product-care instructions, protect snaps and electronics from moisture, and air dry completely. Never place controllers in water, a washing machine or a dryer.
Results, Orders and Support
When will I see results?
Results differ based on the product, placement, intensity, consistency, activity level and individual body. No specific result or timeline is guaranteed. Correct setup and consistent use according to the instructions matter more than using excessive intensity.
Where do orders ship from?
Orders ship from Beverly Hills, California. Free U.S. shipping is offered, and tracking is provided when your order ships. Most U.S. deliveries arrive in approximately 5–7 business days, although carrier delays and remote destinations can take longer.
Can I pay in installments?
Eligible purchases can be split into interest-free installments through the payment options displayed at checkout. Approval and availability are determined by the payment provider.
What is the return policy?
Eligible regular-price items may be returned within 30 days when unused and in their original packaging. A return authorization is required. Sale, clearance, promotional and discounted purchases—including orders placed with an additional discount code—are final sale. Please review the current Return Policy before ordering.
Can I exchange an apparel item for another size?
Eligible unused apparel may qualify for a size exchange, subject to availability. Customers are responsible for return shipping. Contact customer support before sending any product back.
What should I send customer support if I need help?
Include your order number, product name, a description of the issue and a clear photo or short video showing the controller, placement and connections. This helps our Beverly Hills support team resolve setup questions faster.
GYM IN A BOX® — The original since 2015. Patented ToneUp15® Pulse Body StimFit Technology. Designed in Los Angeles and shipped from Beverly Hills.
Always follow the instructions supplied with your individual product. This FAQ provides general information and does not replace product instructions or professional medical advice.