... : high-quality alloy steel4 There are top rollers in the U attachment on the oterside link. Different kinds of attachments are available, ... A2, extend-pin, etc.5. Except manufacturing equipments of the chains, we also have automatic lathes, grilling head lathes, ... So, we have a strong processing capacity of parts to ensure delivery and lower prices. P125 roller chain with top roller in U attachment