The KICKR CORE is the latest in Wahoo's line of smart indoor bike trainers. It delivers a realistic, accurate, and quiet indoor training experience by using the proven flywheel technology and advanced algorithms of Wahoo's legendary indoor bike trainers. The KICKR CORE indoor trainer is built with the durabilty to withstand all of your indoor training sessions and no other brand of smart trainers has more apps and software training options, including Zwift and Trainer Road. Specification : Part Number: WFBKTR4 Dimensions (legs open): 20"L x 23"W x 19"H Dimensions (legs closed): 9"L x 23"W x 21"H Weight (unboxed): 40 lb Rear Wheel Size: 24" RD / 24" MTB / 650c RD / 26" MTB / 700c RD / 650b MTB / 29" MTB Hub Types: 130/135mm QR, 12x142, and 12x148 Thru Axle Adapters: Included Drivetrain: Cassette not included. Requires Purchase/Installation of New Cassette: 8/9/10/11 Speed SRAM/Shimano KICKR CLIMB: Compatible Yes RPM Cadence: Not Included Front Wheel Block: Not Included Resistance Type: Electromagnetic Accuracy: + / - 2% Wireless Software Updates: Yes 3rd Party Power Meter Support: Yes Connectivity: ANT+, ANT+ FE-C, and Bluetooth Devices: iOS, Android, PC (Mac and Windows) Max User Weight: 250 lb Power Requirements: 100-240V~1.5A 50-60 Hz Flywheel Weight: 12 lb Maximum Simulated Grade: 16% Maximum Power Output: 1800W