Nitro SP (Super Premium) is much stronger than the standard ANSI roller chain. This is achieved by manufacturing the chain from a higher grade alloy steel with more heat treatment to the chain components. The SP chain is generally used in high shock loads applications where the chain endures repetitive "jolting" during its operation. The connecting link (master link) plated are pressed fit rather than a slip fit. This is done so the integrity of the chain is not compromised, whereas a slip fit link would create a weak joint.
Offset links are not available due to high demands of the SP chain.