This is a variation of NBA Jam for the Sega Game Gear, specifically version 1.1, suggesting a later release or an updated version of the original. Likely refinements or bug fixes are included compared to the initial release.  The gameplay is expected to remain faithful to the core NBA Jam formula of fast-paced, arcade-style basketball. This version was released in the USA by Sega.

NBA Jam (USA) (v1.1)

NBA Action (USA, Europe)