Headlight Bulb, 12 volt, 45/40 watt with Ba20d base.This is a 45/40w headlight bulb. It will fit any Lambretta and some Vespa with 12v lighting.
The Complete Spanner's Manual: Lambretta Scooters by Martin 'Sticky' Round (Author) Third Edition
The Unofficial Lambretta Manual Update by Mark Haines
LAMBRETTA - ILLUSTRATED GUIDE TO THE IDENTIFICATION by Vittorio Tessera
Lambretta Performance Tuning and Conversions - 8099990