I made screen panels for my
hatches, exactly as Sailormon6 described - with a folded 1-1/2" wide black nylon webbing hem, sewn to each black fiberglass screen panel perimeter. Hardware stores carry this strap material for DIY belt makers - the type used on duffle bags and PFD belts.
To one face I stitched a 3/4" velcro loop strip, the adhesive backed hook strip was then adhered to the
hatch flange. This worked OK for a while, but eventually the adhesive Velcro strip pulls away from the
hatch flange - due to the force needed to remove the screen panel. Velcro's grip is just too strong for the adhesive.
I never really liked the look of the Velcro tape with the screen panel removed anyway. I've been considering other methods for attachment of the panels - with no solutions yet.