There are two types of links alternating in the bush Stainless Steel Chain roller chain. The initial type is internal links, having two internal plates held together by two sleeves or bushings where rotate two rollers. Internal links alternate with the next type, the outer links, consisting of two external plates held jointly by pins passing through the bushings of the internal links. The “bushingless” roller chain is similar in procedure though not in structure; instead of separate bushings or sleeves holding the inner plates with each other, the plate includes a tube stamped involved with it protruding from the hole which serves the same purpose. It has the advantage of removing one part of assembly of the chain.
The roller chain design reduces friction in comparison to simpler designs, resulting in higher efficiency and less wear. The initial power transmission chain types lacked rollers and bushings, with both the inner and outer plates held by pins which directly contacted the sprocket teeth; however this configuration exhibited extremely rapid use of both the sprocket tooth, and the plates where they pivoted on the pins. This issue was partially solved by the advancement of bushed chains, with the pins holding the outer plates passing through bushings or sleeves connecting the inner plates. This distributed the put on over a larger area; however the the teeth of the sprockets still wore more rapidly than is desirable, from the sliding friction against the bushings. The addition of rollers surrounding the bushing sleeves of the 
chain and offered rolling contact with the teeth of the sprockets resulting in excellent resistance to put on of both sprockets and chain aswell. There is even very low friction, as long as the chain is sufficiently lubricated. Constant, clean, lubrication of roller chains is usually of major importance for efficient procedure as well as correct tensioning.