The Manrose PEFLVTT T12T Timer model features an adjustable integral electronic timer (1-20mins) and is designed to power 12V 100mm & 120mm low voltage fans in shower or bath splash areas. The T12 series of Safety Extra Low Voltage (SELV) transformers can be mounted in the loft area or high-up on the ceiling next to the pullcord light switch. The T12 25watt transformer models are suitable for use with 100mm & 125mm Low Voltage Fan Range models such as PEFLVF, XF100LV, XF100HTLVT, WF100LV, XF120LV, and WF120LV. The electrical input is 220-240V - 50Hz, and the output is 12volt AC. 50Hz 25VA S.E.L.V. The transformer must be mounted out of reach of the user, double insulated, and connected to the supply through a suitable double pole isolating switch with a minimum contact gap of 3mm on fixed wiring circuits. The protective fuse should not exceed 3A, and installation must be supervised by a qualified electrician. The size of the transformer is L.147mm x H.86mm x D.66mm.