The company has grown a lot since then!R.A. Ribb Company: Ribb Rakes - Clam Rakes
The bump rakes as we called them used a harness, belt that went around my waist and attached by chain to the top of the basket connected to a 6' alum pole with a T-bar handle, some were adjustable, some were fixed. I would guide the teeth down into the mud and bump my ass back pulling the basket, we would walk backwards for about 10 feet per pull. The only issue was the teeth on the basket, I would snap 1 or 2 about everyother week.
Do they have a shop you can go to in Harwich? I would like to visit next time I;m there. I have an old setup you are talking about but never used it. We call them donkey rakes on Long Island.