I'm just curious but why not ?I keep old empty jugs of gravitex for that exact purpose.
Surely there must be a standard bottle?
With fear of opening a can of worms I also wouldn't put waxoyl near anything I cared about.
I'm just curious but why not ?
Nothing wrong with Waxoyl, always got a pot of it with a brush in to coat fasteners.
All those 1L tins of shutz/underseal should fit your gun so why not buy a 1L tin of waxoyl like your photo, use that & when empty refill it from your 5L can.
my mate used to have an old sauce pan he used to fill with water and stand on one of those little camping stoves with the tin of wax oil in the water and keep it on the boil.i used to heat it with a paint stripper gun up against the tin, used a gallon tin with the top cut off so it was easier to use, mate used to heat up his on a disposable bbq ,applied it scolding hot.