Glassware
Milkshake glass
The fluted soda-fountain glass: a narrow base flaring to a wide rim, so the drink can be overfilled above the line and still be carried.
Capacity
To the brim470 ml
No ice ever goes in it. A milkshake is already frozen and adding ice would thin it.
Every drink below was checked against this figure at build time. A recipe that does not fit its stated vessel fails the build rather than shipping.