Demand from microscopists has led Pyser-SGI Limited to introduce a longer stage micrometer. Calibrations of compound microscopes at low magnifications, stereo microscopes and measurement of fields of view require a longer scale than those traditionally available. This new PS5 has a high accuracy scale of 20mm length, which is subdivided into 10 micron divisions. The scale is produced as a vacuum deposited chrome image on a rectangle of glass, with a coverglass cemented on top. This is mounted in a stainless steel slide mount and is supplied in a polished wooden case. Internationally traceable certificates of calibration are available to satisfy the requirements of ISO.