Pauls Components does it again! No more worries thumb shifter fans! Finally, mount up some thumbs to both 8 or 9 speed mountain bikes! Eliminate your sloppy, overcomplicated new school shifters and take a step back in time to a simpler life.Thumb shifters have always been where it's at! They work with perfection and are always reliable. Try thumbies if your sick of poor shifts and plastic/pot metal garbage that will fail after your knee makes contact.Check out my review of this exciting new product!These shifters (or rear shifter) are perfect for trials riders (stock bike) Unfortunately, you have to purchase both front and rear adapters. Adapters are not sold in singles.