SilencerCo Piston M13.5 x 1 LH Size XL AC626

I have a Sig Sauer P 229 with factory threaded Sig barrel. The Regular piston M13.5X1 LH was a fraction too short for the Osprey 45 I wanted to use with My 9 MM. If you cycle the 9MM the "guide rod" would tap/touch the Osprey. Not sure but felt it could cause damage the Osprey if fired. The piston I got has a Matt Black finish. Hard to tell it is there as it looks like the barrel. Probably a 1/4-inch clearance when I cycle the gun now. Transaction went very well, and they were the lowest price I found. One company was a little bit cheaper but wanted $25.00 for regular 3-to-5-day shipping which I got from WH. Ordered several times over the years from WH and never disappointed.