Radio blanking plates on 750 series Giulietta Spiders were originally silver/black. 101 series Spiders also seem to have predominantly been fitted with this type although some later cars were fitted with the later black type.
 
Part Name: Spider Radio Blanking (Delete) Plate, Silver/Black
Alfastop Product Code: 1CWB175
Original Alfa Romeo Part No: 1495.31.700
Model: Giulietta 750 & 101
Quantity Per Car: 1