This is the MRP XCG Triple Chain Device – 44 Tooth Bottom Bracket Fitting with Integral Bashplate. MRP launches patented XCG Series of impact guards for cross-country bikes. Lots of cross country riders don’t want to give up their big ring in exchange for a crank-mounted bash guard, nor do they want to add a large, heavy bash ring on top of an outer chainring. With an XCG, you can keep the big chainring on and not worry about damaging it on obstacles. The XCG is light weight, and costs a lot less than replacing a high quality 44T ring, so it’s a great accessory for the fast and technically aggressive XC rider or for any rider looking to protect their investment.