Aircooled VW South Africa

Can someone please tell me how the mosquito nets are attached to the windows. I'm talking about the centre row windows. I know the rear hatch has some buttons and some have magnets.

It’s fitted in an aluminium frame, that clips into the window frame.

Thank you Sean, I have the frames an replaced the netting, but cannot figure out how the clip is supposed to hold the frame. Unless maybe it's supposed to be fitted from the outside?... I'm going to try that.