Equipment and Materials

High‐accuracy thickness gauge. A new high‐accuracy thickness gauge, known as Beta 750 (Fig. 1), has been developed jointly by Johnson, Matthey & Co. Ltd., and Panax Equipment Ltd., of Holmethorpe Industrial Estate, Redhill, Surrey, Tel.: Redhill 3511. The equipment is intended for checking very thin coatings, such as precious metals, plated on to other materials. For the electronics industry, in particular, it presents for the first time an accurate means of quality‐testing, with unskilled personnel, items which are usually gold‐plated for high‐grade applications, e.g. wave guide parts, printed circuit boards and relay contacts.