Teng Tools makes most wrenches, sockets and hex keys in both metric (mm) and SAE (inch) sizes.
Which do I need?
Metric — most modern vehicles (including nearly all cars and trucks sold in the US today), European and Asian equipment.
SAE — older American vehicles, some heavy equipment, plumbing and general hardware.
Most professional mechanics end up with both. Teng socket sets and wrench sets are available in metric, SAE, or combined versions.
How to tell what a Teng tool is
Every product listing shows the size system. A 17 mm wrench is metric; a 5/8" wrench is SAE. Our product spec articles list every size in each series.
Not sure?
Ask us here in chat with your part number or what you're working on and we'll point you at the right sizes.