The Checkmate product is clamped onto each individual nut on a tyre and arranged with the pointer direction being the same for all nuts.

If later examination reveals a pointer being of different direction from the remainder, a loosening of the nut is indicated.

The Checkmate griping system has been developed to allow use over a range of different nut sizes. Size 1 fits nuts from 13/16” to 1-3/16” whilst size 2 fits nuts from 1-1/4” to 1-3/4”. The gripping system consists of two sets of triangular teeth forced closed by the tightening of a flexible tie. The arrangement of the teeth has been designed to allow the gripping of both smaller and larger nuts from its un-deformed size.

The tie is simply drawn closed by hand, and if necessary, tightened by a drive pin. The drive pin can also be used to tighten the Checkmate in hard to reach locations.

The underside of the tie is serrated allowing the tie to only pass through the locking mechanism in one direction. The locking mechanism can be manually released allowing the removal of the Checkmate.