The Mini AE sensor is useful where space is at a premium, or direct contact with the rotating part of a grinding or dressing spindle is necessary but a spindle bore is not available. It is a non-contact sensor and can be bolted on either end of a spindle using an M6 LH or RH thread. The AE signal is passed from the rotating sensor across an air gap to a non-contact receiver unit. The direct mounting nature of this sensor gives strong uninterrupted signals.