I have a set of Briley sub-gauge tubes for .735 bore 20ga. Tubes are marked CG Maxis but I have been using them in my Blaser F3 Super Sport as well The 20 and 28 ga. tubes are ultralights and the .410 is a standard weight. They are 31-1/2 in. long making them 32 in long with the extended chokes 20ga. chokes = 2 SK, 1 IC, 1 LM and 1 IM 28ga. chokes = 2 SK, 1 IC, 1 LM and 1 IM 410ga Chokes = 2 SK, 1 IC and 1 LM They will come in a Briley 32in hard case tube-set carrier $1100 David 870-310-3217 saltineice@yahoo.com