5 1/8″ x 12UN No Go Plug Thread Gauges Used

Where this comes from

The part other shops don't tell you. Three separate questions, kept separate on purpose, each with its source.

• UK company

  Registered at Companies House as SHEFFIELD TOOLING CO LTD, number 10323543. Checked 2026-08-29.

  Means the business is a British legal entity, not a British-sounding name owned elsewhere. It says nothing about where anything is made.

• UK operations

  Not yet checked.

  Means people employed here, or premises they actually work from. We keep this separate from the company badge because a registered office can be an accountant's spare room, and a company can be registered in Britain while everything it does happens somewhere else. Where we have not looked, we say so rather than assuming.

• British-owned

  Not established. Many companies file a statement rather than naming a controlling shareholder.

  Read from the register of people with significant control, following the chain of holding companies. It does not gate anything: a firm can be made here and owned elsewhere, and that is worth telling you rather than hiding.

• Where it is made

  The maker doesn't say, so neither do we.

  This is about the individual product, not the company. A British firm can sell things made abroad, which is normal and not a criticism. We would rather tell you which is which than average them into a score.