TECHNICAL SPECIFICATION: Hardened and Tempered, Chrome Plated, Shallow offset, Strong and thin walls, Conforming to IS 2029-21998. Each spanner piece of the  De Neers double end shallow offset Ring spanner set feature a looped end instead of an open one, which grips rotary fasteners tightly from all sides. As the name suggests, different sized rings are given on each end of the spanners in the set. To use it, one needs to simply slip the ring around the nut or bolt, and turn to loosen or tighten. The offset design ring are cranked at 15 degree for ease of operations. You can order any set with 8 / 10 / 12 ring spanner set www.samsindusneeds.com and get it delivered at home. HSN CODE: 82041110. PRODUCT CODE: 13-8M.