The No.4 Mk2's are the later ones that are easy to tell by looking at the stock bolt at the end of the fore-stock just in front of the wrist, it will be a small bolt that is adjustable and removable with a screwdriver while the No.4 Mk1's will have a riveted metal clamp in the same place. Also the Mk2's have the trigger mounted to the receiver instead of the trigger guard like the Mk1's do.




















































