Because the lashes are held on with magnets, this means that they are unaffected by water. Magnetic lashes will remain attached even if they get a little wet. This doesn't mean you can go swimming in them though. If they get thoroughly waterlogged, the weight of the water will pull the lashes out of place. So you can get in the pool with them but if you are swimming laps or in for some serious water play you may want to leave your magnetic lashes at home.