Genuine Lucas Temperature sender unit, suitable for both 12v & 24 v models, can be used for oil or water temperature gauges. Thread Size 5/8" UNF OEM part references SNB125, 560794, 555843, TT4801/00A Suitable for Land Rover Series 2 - 3 2.25 & 2.6 all models including Military FFR 24 volt models. Series 2a 2¼ Petrol from engine suffix 'J' onwards 2¼ Diesel from engine suffix 'H' onwards 6 Cylinder engines Series 3: 2¼ Petrol, Diesel & 6 Cylinder Engines Defender 110 1983-84 Oil Temp on Range Rover Classic early V8 models. 8.5:1 & 8.25:1 Compression Engines (Suffix B - 1985) with 120 degree gauge Plus a huge range of other classic vehicles Available with optional 546177 adapterFits Imperial Engines only from late 2a (Suffix H) until Engine number 36619420B (around 1970 - June 1980) Also fits earlier 2.25 diesel, exchange for 278164 blanking plug SNB125, 555843, GTR111, VE718038, ST410884C, 31110, CTS6078, 02877229, 52770, C15472, STT009, 1342557, XTT49, 13H5602, 161510, 560794K1, E1C9988, TT4801/00A