The Karsten adjustable cheekpiece is designed to be attached to an existing stock. The model B version has a flush fitting allen head instead of the hand tightened knurled knob on the model A. It does require an allen wrench to tighten (Allen wrench not provided). It can be used by both left and right hand shooters and it has fixed notches to lock the cheekpiece at a certain height. These cheekpieces are manufactured here in the USA with high quality Kydex thermal plastic. They are durable and quite functional.
For a full review with many pictures of installation, visit our review page.