100% Cotton Mops are ultra absorbent. They hold and carry solvents, lubes, and preservatives into your bore and chamber. Great for applying large quantities of modern copper solvents to fouled bores. Small Rifle Chamber Mops fit 22 Hornet, 222, 223, etc. Large Rifle Chamber Mops fit 22-250, 308, 30-06, belted magnums, etc.