Usually I can get at least 2 full leg wax's from one large roller cartridge.
I use Clean & Easy spa system, but find when browsing most others are approximately the same size's.
Compare content. ie: 500ml - 500grm.
You'll find most are equal.
There are units with spray on parrafin & roll on cartridges in the one unit.
Different heat settings also, so you can control the tempreture to the wax you're using
I think the main difference with these, is the size of the unit lid as it has to accomadate the spray nozzle.
I prefer the roll on, less mess & fuss.
We do use hot wax the traditional way as an alternative if clients request.
HtH
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