You can use a variety of lubes with the Fleshlight but certainly not all.
The most important thing to keep in mind about any lubricant you use is that it is a water based lube.
Using anything other than a water based solution can destroy the texture of your sleeve.
That’s because any other liquid bases will not wash off when you run it under water and dry into the skin of your sleeve, slowly start reacting with it upon storage.
If you’re not sure when purchasing, look at the back of the bottle and it should specify the liquid base.