Replaceable HRC fuse to allow replacement if damaged by the failure of GZ/GU10 lamps. Suitable for control of dimmable electronic transformers, toroidal transformers and tungsten lamps WITHOUT de-rating. Not suitable for use with fluorescent lamps. Leading edge phase control. For use with resistive and inductive loads. Integrated over-temperature protection fuse. Module case ultrasonically sealed to reduce. dimmer buzzing. Smooth dimming operation from 0-100% light output. Fits a plaster depth (16mm) mounting box . AU-DSP251/252/401/402RF. One or two way switching. Complies with the latest Electrical Safety standard for dimmer switches EN 60669-2-1:2000. EMC compliance - EN 55015. 1 Year guarantee.