Harbor Freight sandblasting cabinet...

The local chinese tool company up here (Princess Auto) sells those clear window protectors. Its a consumable for the cabinet. The glass should be tempered and not cheap to replace. If its a siphon cabinet they don't work worth crap without mods. Just google 'cabinet metering valve mod'. It makes a huge difference in performance and stops plugging. I run the cabinet with about 2 cups of media in it.
Please explain why the glass should be tempered? I just replaced my glass (non-tempered) and the glass business suggested to not use tempered glass as if it breaks it will basically crumble (shatter like a tempered shower door) and require the media to be replaced. They made a 1/4" replacement for me. Normal use doesn't put force on the glass, and I always use the stick-on clear covers on the inside that can easily be replaced when they get cloudy. I see no advantage or need to use tempered glass, 1/4" glass with the plastic inside cover is very durable.