1.Perfect self-checking function 2.Immunity 3.Durable life 4.Good anti-vibration and easy to use 5.Self-locking function STD seriesProtection range, 0-10000mm;Specification STDxx10 (xx=24, 32, 40, 48……136) STDxx20 (xx=08, 12, 16, 20……72) STDxx40 (xx=04, 06, 08, 10……40) STDxx80 (xx=02, 04, 06, 08……40)Light axis pitch10mm, 20mm, 40mm, and 80mmProtection height Height=(xx-1)×light axis pitch STDxx10 ...