Bluetooth-connected weighted jump rope handles designed for high-intensity interval & endurance fitness training AMP handles incorporate smart technology to track jumps for personalized & guided full-body workouts Burn calories faster: Crossrope App provides personalized jump targets, benchmarks and stats tracking, plus Free Jump Mode. Membership activation instructions delivered upon product receipt Elevate performance training in major muscle groups: real-time jump counting technology & feedback Compatible with Crossrope weighted jump ropes and ropeless (ropes and ropeless attachments sold separately) Crossrope AMP 2.0 Smart Jump Rope Handles– Bluetooth-Connected, High-Intensity Fitness Training for Calorie Burn and Cardio - Membership Required