trouble using bondo

Not a body guy, but my car is getting done by a guy that worked in a shop for a 10 years or so. He has used several different products on my car. From what he told me what he uses will depend on what he is doing. I know he is using a product called Rage on my car. But he has mentioned several other ones. He did mention that where he had to make a patch panel on the 1/4 after welding he did mention a product called Duraglass, if I remember right. I know the one thing that is required is patience, which leaves me out of doing body work......