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On Site Services (Calibration) Ltd are proud to offer a range of precision granite products that are manufactured using high quality, fine grained black granite.  These are precision finished by hand to ensure they are of the highest quality.

There are many advantages to using fine grained black granite in all aspects of engineering and measurement, from shop floor and work holding to accurate inspection and calibration. In a forever advancing industry it is important that reliance can be placed on all measurements taken. Our precision lapped granite products are produced to the highest accuracy to aid in this confidence of measurement.

The main advantages of introducing and using granite measuring equipment are:

  • Does not rust.

  • Non-electrically conducting.

  • Less susceptible to burrs.

  • Does not directly contribute towards “metal to metal” cross contamination.

  • Non-magnetic.

  • Not as susceptible to environmental changes such as humidity and temperature.

We are also able to offer bespoke services on all granite products from large surface tables with multiple threaded inserts to individual granite artefacts as per customer drawings. So if you have any special requirements, please do not hesitate to contact us. Our skilled team are on hand to answer any questions.

Granite Master Square

Our highly accurate Granite Master Squares are supplied with 4 face straightness, flatness and parallelism. They are also supplied with weight reducing holes to aid in the movement and handling while being used and during transportation.

Granite Parallels

Our Granite Parallels are provided in matched pairs with 4 face parallelism and flatness to offer the most versatility and usability.

Granite Straight Edge

Our Granite Straight Edges are supplied with 2 faces straight and parallel. For products 1000mm and over, weight reducing holes are included as standard to aid in the manoeuvrability and use of these items.

Granite Surface Plate

Supplied in accordance with the flatness tolerances in BS 817: 2008 for Grade 0 and Grade 1, our Granite Surface Plates & Tables are the basis for many measurements and are a must have for laboratories, inspection departments and for general shop floor use. 

Granite Triangular Square

Our precision Triangular Squares are manufactured to highest quality and offer an excellent solution to checking squareness. All Tri Squares are supplied with bored holes to reduce the weight and aid in the use and positioning of the product. 



To support our range of granite measuring products, On Site Services (Calibration) Ltd also offers the below Accessories


Granite Surface Table

All Surface Plates 900mm x 600mm and larger are provided with a heavy duty box section frame consisting of 3 primary points of levelling and an additional 2 secondary supports for stability. To ensure adequate load bearing, larger surface tables will be provided with additional supports as necessary. 


On Site Services (Calibration) Ltd
10 Cavendish Avenue
NG21 9NQ

Thank you for your enquiry.​

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