Five bottles, 118 ml (4 fl oz) each — 590 ml in total. Water-based, so it is the one to use with silicone, including the dilator set and the kegel weights.

what it is
A water-based gel with no parabens, no glycerin and no added fragrance. Light rather than tacky, and it rinses off with water, which means no residue left on silicone and nothing to scrub out of fabric.

water-based or silicone-based?
Silicone lubricant breaks down the surface of silicone over time, so it should not be used with silicone products. Water-based will not. If you own the dilator set or the kegel weights, this is the one that goes with them.

how much to use
More than you think. Too little is the most common reason a dilator or weight session is uncomfortable, which is the main argument for keeping several bottles in the house rather than rationing one.

other sizes
A single bottle, or a three-pack.