ALL Huntsman frames, even the blued and the Nickel frames? KODY
There is one SB2 Huntsman frame, ONLY the one that came as a .50 cal/.243 cal Huntsman Combo from NEF. All the rest including the .50 cal/12 ga Tracker Huntsman Combo, and .50 cal/12 plain barreled Huntsman Combos, and ALL nickel framed Huntsmans are SB1. They did make that combo in 2003, but unless your NT frame was originally a combo (doubtful), it is a SB1 frame like quick said. You could determine an SB1 frame from a SB2 frame by looking at the differences in the FAQ's, but the best bet is to call Customer Service with the serial #.
By the way, both SB1 (Standard/12 ga Combos) & SB2 (.243 Combo) Huntsman frames were color case hardened for the blued barrels at that time.