Colonial Arms 12gauge Screw-In Tru-Tube Choke Tubes

Beautifully made tubes with an extremely smooth inside finish and an undercut, tube-to-barrel joint to minimize shot and wad fouling buildup. Both Win-Choke and Tru-Choke tubes are "invisible" style, no unsightly "knob" sticks out. And, they can't rust; they are stainless steel. Install/remove with a quarter. WARNING: FOR USE WITH LEAD SHOT ONLY. Mfg: Colonial Arms SPECS: Approximately 1-1/2" (3.8cm) long. Stainless steel. Threads are as follows – Tru-Choke-style Tru-Tube 10 gauge are .865"-44, 12 gauge are .795"-44, 16 gauge are .718"-44, 20 gauge are .675"-44, 28 gauge are .613"-44 tpi, .410 are .478"-44 tpi.