These are correct size endcaps to make authentic TNT blocks. The US Army manuals state that TNT blocks are 2x2 width, but this is just a nominal measurement. The actual size of originals is 1 3/4 in x 1 3/4 in. To make that well you need to use a block of wood slightly narrower than that (make it match the narrower step on my end caps) with .25 radius rounded corners (use a router table). Overall length of assembled block should be 3 5/8 in., so you need a 3 inch long block. the cap well hole is undersized so you can drill it out to get a more consistent shape. Do this after gluing to the wood so that you can drill the hole in the block at the same time for perfect alignment. Please don't use these for green label 1/2 lb. or 1 lb. TNT because those blocks are supposed to have threaded cap wells, which I will make a file for soon.