Shimano grip shift 6 speed Clearance

Product Name: Shimano grip shift 6 speed Clearance
microSHIFT1-6 Speed Right Bicycle Twist Clearance, Microshift MTB Bike Bicycle Twist Grip Clearance, My daughter's Trek came with a 6-speed Shimano Revoshift SIS Index. It's a new bike. She can shift to higher gears easily but does not have the grip strength to shift back Clearance, microSHIFT1-6 Speed Right Bicycle Twist Clearance, Amazon.com : ZUKKA Revoshift Right Shift Lever,SL-RS35-6R Tourney Twist Grip Gear,6-Speed Bike Handle Shifter,MTB Mountain Bicycle Derailleur Transmission : Sports \u0026 Outdoors Clearance.