Complete with cap & internal pipe. The cap is 59mm diameter, similar to that fitted to 1960 Giuliettas. Some earlier bottles seem to have had a smaller diameter cap, which is no longer available.
 
Part Name: Tudor Windscreen (Windshield) Washer Bottle
Alfastop Product Code: 1CWF117
Original Alfa Romeo Part No: 1493.86.718
Model: Giulietta 750 & 101
Quantity Per Car: 1