The Mark 5 stock reduces felt recoil and muzzle climb to make follow-up shots faster and more accurate. Single-handed firing is also be made much easier. The stock is made of tough fiberglass filled plastic and comes with a soft 1" rubber recoil pad and a quick detach swivel stud. These stocks have Choate's innovative spacer system and come with two 1/2" spacers included which adjusts the length of pull from 13" to 14"