The Advent Master precision tape measure is EC Class I accurate, Class 1 rated tapes are the most accurate and an error of no more than ±1.1mm over a 10m length can be anticipated, where a steel tape is used with a pulling force of 50N at 20°. The tape features a 25mm wide metric and imperial non-reflective blade and is manufactured from high grade steel. End clip secured by 3 rivets for durability. ABS case with a heavy duty locking mechanism.