Based on the successful 6310 design that's been well proven on many of our Dead Air Keymo and Xeno devices, 6310 is a closed bottom flash suppressor / muzzle rise compensator that provides 15 to 20% better compensator performance, without the extra muzzle flash, concussion and noise normally associated with a compensator. 6310's shorter and smaller 3 o'clock and 9 o'clock ports force more gas to be vented through the 3 upward facing ports.6310RF, like all 6310 family of flash suppressor / compensator, has a closed bottom, which requires timing to ensure the center port faces 12 o'clock dead center.We encourage you to visit this page for more of our thoughts on closed bottom muzzle devices: https://www.forwardcontrolsdesign.com/the-case-for-closed-bottom-muzzle-devices.html6310RF has external 0.900 x 24 threads, compatible with sound suppressors with 0.900 x 24 threads and adapters such as Rearden's Atlas adapter.*All of the RF devices will stop having the FCD and Revival Defense logos engraved on the bottom. 3P15 (also a Plan B compatible device) has already done away with it, the upcoming, new Plan B compatible device will also similarly hve no room for them. To keep things consistent, 6315RF, 6310RF, 1215RF and 1210RF will omit the logos as well. As an added (though unplanned) benefit, the omission of the logos gives them a cleaner look as well.*