Chances are that the letters TA represent the words take apart.Which infers take down.The only production model 39 rifles with this feature were the original models made from 1922-1938.The label of 22SLLR indicates that your rifle can fire all 3 cartridges,the 22S(short),22L(long)or the 22LR(long rifle).It should be noted that you may have a promotional model that was made sometime later in the production span of the model 39.I would advise contacting Marlin directly for more specific info on your rifle.