Far better at driving stakes into rocky ground than any Rock at hand, the MSR tent stake Hammer features a hardened stainless steel head and is engineered with a perfectly balanced swing weight. Just 11 ounces, the tent stake Hammer also features an integrated bottle opener-so you can celebrate all the energy you saved, plus your ability to truly leave no trace. MSR products are covered by a three year limited warranty against manufacturing defects in materials and worksmanship.