Quick guide from Laylax showing how to install the MP7A1 Lightweight Rail Set for the Tokyo Marui MP7A1... "A set of top rail and side rail for Tokyo Marui electric compact machine gun and gas blowback machine gun MP7A1. The main body is greatly reduced in weight by manufacturing it by aluminum shaving. It improves handling during the game and reduces fatigue. The design that does not change the rail height or appearance has a high affinity with the air gun body, and it can be said that it is a rational option that improves performance without impairing the original image and usability of the MP7."