The PNW attaches to the Atlas adapters, making them compatible with most suppressors on the market. Please note these are not compatible with all suppressors. The length may be too long for the blast chamber of your suppressor. The PNW can be used to bring a 13.9" barrel to 16" length. If using this to pin and weld a 13.7" barrel, you must use a precision washer of at least .030" to meet the required 16".