29" Bicycle Rear Disc Wheel With Double Black Wall Alloy Rim, 160mm Brake Rotor, 7-Speed Freewheel 14-38T and 2.25" Tire 29er Mountain Bike. This wheel's freewheel is made for bikes with a 1x drivetrain (single chainring crank) The rear derailleur will need to be compatible with a 14-38T rear 7-Speed freewheel.