TUFF STUFF by MUSTAD options 7.5 OZ - $15.99 7.5 OZ Size 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Please call the store at (434) 392-4192 to place your order. Mustad Tuff Stuff strengthens brittle, shelly, mushy or cracked hoof walls. Use to guard against fungus, caustics and bacteria and maintain the hoof wall's natural moisture level.