The Engineer TS-04 is a great set of light duty spanners - just 1.5mm thick, they're precise, pocket-sized and portable Supplied on a (detachable) chain, this set is ideal for those situations where only the thinnest of spanners will fit! 8-in-1 stainless steel spanner set 1.5mm super thin head & shank 30 degree inclined head (at one end - the box end) Material : Stainless Steel (SUS420J2) Hardness : HRC 52±2 Size Length Weight Box Open Spanner 1 4.0 3.5 100 8 g Spanner 2 4.5 4.0 Spanner 3 5.0 4.5 106 10 g Spanner 4 5.5 5.0 Spanner 5 6.0 5.5 Spanner 6 6.5 6.0 114 12 g Spanner 7 7.0 6.5 Spanner 8 8.0 7.0 Please note: whilst the manufacturer has used hard grade stainless steel material for this product, the spanners are only intended for light usage - there's a limit to how much you can push a tool that measures just 1.5mm thick!