BA15d (15mm base)(pre-BPF) headlight bulb LED 6v to 24volt [6v, 12v] 20/40W (nominal wattage) negative or postive earth, suits headlight pre 1946 with no flange on bulb base, parallel pins, uses approximately 0.5 Amp on low beam, 1 amp on high beam, each. Overall length 65mm; max width 25mm; length from base to front 45mm. Does not have the same beam pattern as original bulb, Tested in local bikes on rallies and tours. LED lamps require a perfect earth to work. If in doubt run a separate earth wire from inside the headlight shell back to the battery earthing point on the frame. Do not rely on old wiring that often earths through the steering head bearings.
