The 1949 Tula was the very first production SKS45 and has a lot of unique features, pair that with the fact that very few were imported into the US and that is why this carbine is extremely collectable! The 49' has many features that are not seen on any other sks, here is a list of the different features and each will be discussed in more detail with pics further down the page. Probably the most notable difference is an original 49' will have a blued 4 lobe spike bayonet, 90 degree gas block, looped takedown lever, hand etched top cover stampings.
Hand etched top cover stamp.
90 Degree Gas Block
Looped Take Down Lever
Spring loaded firing pin and 49-50 specific bolt assembly.