Yeah, the Thai version had fixed undercarriage, but had a different armament. It featured 4 mgs in the wings, that according to most publications were soon changed to 2 madsen 23mm cannons (as in the american XP-36F variant). The cannons could be quickly exchanged by ground crews to small bomb racks for limited ground support missions. Thus the 75N was a much better armed and more versatile variant than the chinese fixed undercarriage counterpart. It also lacked the radiocompas element of the P36G.