This is for connecting rubber bands to create bracelets, etc. Regarding the quantity, I don't know the exact number of pieces or grams, but it seems to be about 100 pieces per bag on average. It comes with S-hooks to connect the rubber bands. I checked the product, which I purchased 5 or 6 years ago. When I took out one from each bag, the rubber bands weren't sticking together, and they didn't break when stretched. Instant purchase is welcome!