The trombone bushing/shim kit provides an extra pair of Bushings with screws and three sets of shims for use with the Neotech trombone grip; . It's great for musicians who want to use the trombone grip; with a second instrument. The bushing remains on the instrument so you can move the grip to a second instrument in a matter of seconds. The kit is available in three options straight Brace, gusseted straight Brace or curved Brace. Select the option that's right for you! .