The mountain handlebar grips provide an excellent grip in all riding conditions including wet conditions. * Easy to romove and install, comfortable and durable. Material: non-slip rubber,aluminum alloy.(Install note: Because the meterial of the lock is aluminum alloy, you should stop twist when it should stop to avoid slip.) * Both of them are suitable for 20mm-25mm (0.79-0.98 inch) in diameter handlebars. * The holder is suitable for all Garmin NUVI GPS models as well as the Streetpilot c510, c530, c550, c580, i2, i3, i5 GPS AND Garmin NUVI 200, 200W, 205, 205W, 250, 250W, 255, 255W, 260, 260W, 265T, 265WT, 270, 275T, 300, 310, 350, 360, 370, 500, 550, 600, 610, 650, 660, 670, 680, 710, 750, 755T, 760, 765T, 770, 775T, 780, 785T, 850, 860, 880, 5000 GPS. * Kit includes: 2 x Mountain Handlebar Grip(with 2 lock rings and 2 end plugs), 1 x Motorcycle/Bike Handlebar Holder For Garmin(with a rubber strip).