We are based in Coventry UK; established in 1991 after the closure of Haycock Gauge & Tool. Following the same traditions we are committed to providing the best quality products and services to all our customers.

We supply a wide variety of precision gauges from screw thread to gap gauges. In addition to these products we also stock a variety of cuttings tools and taps. As one of the leading suppliers of these products we have customers across the UK as well as across the globe.


Mercury is very proud of our heritage and continues to provide support to the manufacturing and supply of precision products across a wide variety of industries including Aerospace, Oil, Pharmaceutical and Automotive.

Uniquely concentrating on both taps and precision thread gauges Mercury offers a complete solution to your machining and gauging needs. Mercury supply an extensive range of products that are manufactured to meet the most demanding quality needs in today’s market.


We are a supplier of Gauging for Anaesthetic & Respiratory Equipment including gauging requirements to satisfy ISO 5356-1:2015.


Mercury Tool & Gauge are ISO 9001:2015 accredited through NQA Certification Limited (UKAS 015), which provides our customers and potential customers alike with the confidence that we have a commitment to quality and customer service, and comply with an internationally recognised standard.

Quality Policy

Mercury Tool & Gauge strives to deliver total commitment to our customers and their requirements. We define quality as conformance to our customer’s needs, and conformance to all quality requirements.
Our performance as a team ensures the customer gets what they want every time and we are dedicated to achieving the highest level of customer satisfaction.
We will achieve this by:-
  • Knowing who our customers are and what they want – through open communication.
  • Understanding the requirements of our jobs and the systems that support us – through training and education.
  • Making continuous improvement a part of every day and every job – through the use of team participation and measurements.
  • Ensuring that our Quality Management system reflects what we actually do. Reviewing areas for continued suitability.
  • Remembering that we are here because of our customers! They must always be our top priority.
  • Being willing to offer any advice & assistance through our knowledge and experience of gauges & tooling which will enhance our relationship with our customer.


Screw Thread Gauges : These are manufactured in accordance with British Standards, ANSI /ASME and ISO standards and a wide range of National and customer supplied standards . We can supply a wide range of thread forms and classes (including ISO Metric, Unified, BA, Buttress, ACME, BSP (G Series), BSPT, NPT, NPTF & ANPT, internal and external gauges, with fully traceable in-house certificates.

UKAS certificates to ISO 17025 are also available upon request.

Special Gauging & Gauging Fixtures : We offer a range of high quality special fixtures products, from plain ring and precision length gauges to bespoke gauging fixtures to customer’s designs.