G3/4 threaded removable spindle with field replaceable adapter threaded shaft to minimize downtime Optical sensing, dual isolated outputs for redundancy. Hollow air vent 14mm EX Explosion-Proof Encoder EX II 2G Ex ib IIB T4 Gb Robust aluminum housing - Extremely high resistance to vibration and shock - Degree of protection IP65/IP66 - Shaft made of stainless steel