We kept our builders in mind with this essential kit for your next project. The LM556BTK is ready to install in your stripped lower. Kit ships with a dry film lubed, Mil-Spec 6 position tube, standard buffer spring, 3oz buffer, standard castle nut and an LMT QD receiver end plate. This kit saves you valuable funds by allowing the user to find the stock of their choice.*Remember proper torque spec and staking is strongly suggested when installing this kit.