Consists of a chuck body and four contact arms. Designed to check run-out or concentricity, straightness and alignment. Will indicate the position of a datum point on a component or fixture from the centre line of a machine spindle. Suitable for use on drill presses, lathes, milling machines, borers etc. Chuck Body: Held in the spindle using a suitable drill chuck or collet chuck (fig 1). The contact arms are retained in position using the knurled collar which lightly clamps the ball joint inside the body. Arms may be exchanged without the need to remove the body from the machine spindle. Universal Indicator Holder The detachable end will allow clamping with 2 and 3 piece dovetail clamping assemblies and when removed will fit standard 1/4 side clamp. This uses the spindle centre line to align component bores or spigots, check the flatness or squareness of workpieces or fixturing and check run-out of components. The spindle should only be rotated manually to avoid damaging the di