Melco Double ended box spanners are thinner than a socket and are much longer so that they can be used to loosen or tighten bolts and nuts in narrow recesses, meaning that they are often used in plumbing maintenance and automotive repair.

The tubular box spanner is manufactured from bright plated steel and is able to accommodate a tommy bar.

The Melco TA21 A/F Box Spanner is made with 3mm steel and has the following specification:

Size: 1 x 1.1/8in.
Length: 180mm (7in).