Box Spanner Sets
Box spanner sets are hand tools that include an array of sizes of box spanners, which are a tubular spanner type that encapsulates a fastener head from above and works in conjunction with a tommy bar, which the operator places through holes in the spanner, to get greater leverage when turning a fastener.
Mechanics and plumbers likely have a box spanner set, as this provides them with a range of sizes to tighten or loosen fasteners in tight spaces.
