The mighty Norse hammer man begs you, don't buy hammers though the mail order!!! The typical cost of shipping one of these is $35.00. That's more then the cost of a 10-pound sledge hammer with a 30-inch handle at your local big box! Two of these monsters would cost only around 50 bucks. And, when you're not banging an imported POS bench back into square with one, you could use it for an intense shoulder and forearm workout.
Figures A, B, and C above show hammers in place of dumbbells for front, side, and rear delt raises. Figure D shows front and rear forearm leverage moves. You can adjust the “weight” simply by moving your hand up the handle to reduce the resistance, or choke your hand down the handle to increase the resistance. By the time you work up to the end of a 30-inch handle, with your moves totally under control, you'll have rotator cuffs of steel and a “tear your heart out” grip. When not training, use them for building equipment and doing chores.
I'm back to Valhalla dudes!