Comments:
The lager can - is there for purposes of giving you scale only!
The biggest plug, on the right, is effectively 6" (15cm) long and has a maximum
circumference of 7" (18cm). The neck has a circumference of 5" (13cm).
Both ball-plugs have a max circumference of 6.5" (16cm) and neck of 4.5"
(11.5cm). Oddly, the single ball is more of a challange than the double
one, maybe because the neck is very short indeed - hardly has one at all!