The HMR-11 features two domed rectangular faces (9mm x 13mm & 7mm x 13mm) polished to a mirror finish.  Like all raising hammers, they are used to shape the metal without thinning or marring it. For raising sheet metal into a bowl against a wooden stake or metal T-stake. Can also be used for raising cylinders and concave shapes and planishing subtle concave shapes.  Fretz casts their hammer heads from 420 stainless steel and tool hardens them to 50 HRC. The handles are made from oiled hardwood shaped and weighted to balance the head perfectly.  Made in Vietnam.