That is an early M-114 APC. Designed for reconaissance, carried a crew of 3 or 4 and was powered by a Chevy 283 V8. We had them with the 14 ACR in Fulda Germany (1962-64)and they were discarded as fast as they could get rid if them. On the road they were OK but off road they were absolutely useless. The M-114 had very poor cross country performance, not a good ride and the tracks were a problem. The tracks were in sections of 8 or 10 ( if my memory serves me) and were not very strong. There were other versions with outside or inside control of the cal 50 MG, or carrying a 20mm Hispano auto cannon in a redesigned turret. Firepower was good but according to some 114 crewmen I knew, the turret-gun combo had many problems. Armor was, like the M-113, aluminum and it was amphibious. It was a miserable flop as a combat recon vehicle, but popular with collectors because it is small, runs fast, not overly expensive and has a popular easy to fix engine. Plenty of junkers out there to get track.