Thinking of installing an R-Hop set-up on your MTW rifle? Instead of modifying your stock ARM by cutting /sanding which may run the risk of an unbalanced force pressing on the R-hop patch - our R-HOP arm is designed to be a drop-in upgrade to mitigate the risk to give a perfect, TDC (top-down-centre) evenly forced pressure. Features - TDC Top-down-centre force applied evenly on the R-Hop patch. - No need for modifying the stock arm and adding M-nub (our arm provides both!) - Easy drop-in with no modifications required. - M-nub provides an even distribution of force applied across the whole surface of the R-Hop patch. - Tough Polycarbonate Construction.