For sliding fly screen doors? My parents have some as they have a pool (you legally have to have a self closing doors that look out on pools) but they aren't magnetic, they have a weight drop thing. If that's what you're after?
Helle it's for a normal door not a sliding one. They're more like a curtain ITMS. With magnets down the centre so as you walk through it closes behind you. We have no screen door at the moment and thought it might have been a quick, cheap alternative to getting a screen door fitted. Pfft, cheap and quick should've been the give away there LOL. DS loves to go outside and we've been leaving the back door open for him. Because of that the house is filled with flies which I hate! The dogs could let themselves in and out with these things too. Oh well I'm glad I asked before doing an emotional impulse buy Proper screen it'll be now, and putting up with the flies until then grrr.