These encoders have robust metal enclosures and double ball bearings so they can survive the abuse that top tier robots dish out. We have included couplings that make mounting easy fit to the applications that you need. Lower pulses per revolution for high speed include 8mm couplings. Higher pulses per revolutions for lower speed applications such as drive train shafts (not included) include 1/2" hex couplings. Encoders have an approximate 20kHz pulse rate limit. Pick rigid couplings when the encoder will be floating. Pick flexible couplings when the encoder will be securely mounted.