These are the first and only 4.3 aluminum tornado threaded barrels on the market. They come in a wide selection of colors, have threads for a tracer, and include O Rings with special cut outs for built in barrel stabilization! They have an LA Capa Customs engraving for them and are produced by us. 7075 Material: Silver, Black 6061 Material: All other colors (in order to color match) Please view this YouTube video for proper fitting and setup of your barrel: https://www.youtube.com/watch?v=j8mZuNQvmco