From RMC Manufacturing. These touch hole liners can help improve ignition over factory liners. Allen wrench installation and removal. Allen wrench included. Available in 4 sizes. 1/4x28 for Thompson Center & others No. 23020. 6x.75 mm for Lyman and other Italian muzzle loaders  No. 23083. 8x1.25 mm fits Pedersoli No. 23187. 10 x 32 fits CVA & Traditions No. 23188