The differences between the original Soviet SKS and the Chinese version are mostly slight and cosmetic. They include different markings, slight design changes and an altered bayonet style.
The Soviet SKS-45 is a gas powered, semi-automatic rifle chambered for 7.62x39 millimeter ammunition fed into the rifle with a 10-round stripper clip into a box magazine. Like many Soviet weapons, including the AK-47, the SKS was reproduced in many Eastern Bloc and Asian countries. The Chinese variant has special significance because its use in the Chinese army was much more prominent than in Russia, where the SKS was almost immediately replaced with the AK-47.
The Chinese Type 56 did not have the milling of the Soviet version, and instead had stamps on the bolt carrier and/or receiver. There are also differences in the thumb rest near the take-down lever, and some Chinese Type 56 models have a spiked bayonet as opposed to the blade-style Soviet version.
Throughout production, the Type 56 was continuously modified and improved, so more tweaks are seen as the production period continues. The Chinese also manufactured hybrid models that blended SKS features with other Soviet weapons, like the AK-47 and the Dragunov. They feature various extras like folding stocks, three-round burst capabilities, and magazine and ammo modifications. As of 2014, the SKS and Type 56 are both in use as ceremonial or militia weapons.