#13 Bore Cleaner and 100% cotton patches: combined they work to clean fouling from muzzleloaders. By offsetting their position on the jag, centering them or doubling the patch thickness, a variety of calibers and gauges can be accommodated with this one size. 2-1/2" diameter. Works well with 45 to 58 calibers. Jar of 100. Mfg: Thompson Center