C
What system is it?
It's a tuff form tray and homelux membrane I have not put anything on it yet so don't seal it in any way?
mapegum wps is magic.Don't know if this will help you out...
View: https://www.youtube.com/watch?v=8ObrNvJCfEg
View: https://www.youtube.com/watch?v=zi0x-XLesQk