Patent ID: 7673542

Claim:
A spanner wrench comprising: a. a handle; b. a head attached to said handle that defines a box end having an inner periphery having a plurality of wall faces connected by a first plurality of corners, said wall faces and said first plurality of corners defining a first polygonal receiving space bounded at the top by a first open end and at the bottom by a second open end, each said wall face including at least one groove formed therein, a second polygonal receiving space defined by said grooves that is bounded at the top by said first open end and at the bottom by said second open end, and c. a radially inward extending ledge disposed within said second polygonal receiving space and located in fewer than all of said grooves proximate said first open end, wherein, when a work piece is received in said second polygonal receiving space, said radially inward extending ledge prevents said work piece from passing through said first open end, and when said work piece is received in said first polygonal receiving space, said work piece can pass through said first open end.