Designed specifically for use with any of the in-line T/C muzzleloaders when using magnum charges of up to 150 grs. of Black Powder or Pyrodex equivalent. 10 gr. increments. *NOTE: Powder measures & flasks are to be used with Black Powder or an approved black powder substitute such as Pyrodex. All implements must be used in accordance with the instructions printed on their packaging and those found in our Safety & Instruction Manual. If you don't have a manual for your Thompson/Center firearm they are available free by contacting the company or via download from our web site.