Measurement of distance between walls - requires rigid telescopic rule with graduations on profile protected lateral face

摘要

The telescopic rule has a rigid assembly. It is easy to use to measure the distance between two walls or between floor and ceiling by extending it until the two ends are in contact with the two walls. The rule has a U-shaped profile and is manufactured from an aluminium alloy or plastics material. A rod (2) slides within the profile and is held in position by ring clips (3) while an end ring (4) carries a tongue (5) to form a brake. The graduations are drawn on one of the lateral faces to be protected by the profiled shape while the rule is not in use.