This Casa Lambretta horn cast for LIS, SX (up to Feb. 1968 1st Version, TV Series 3 is unpainted and without a grill.
horncast cover casing
The Unofficial Lambretta Manual Update by Mark Haines
LAMBRETTA - ILLUSTRATED GUIDE TO THE IDENTIFICATION by Vittorio Tessera
Lambretta Performance Tuning and Conversions - 8099990
Lambretta Tuning Manual by Dave Webster - 8099992