This is an M48 tank, almost certainly an M48A3. The gun is still the same 90 mm M41 model found on earlier versions, although it was eventually replaced with the 105 mm L7 (on the M48A5). The commander’s cupola is also the M1E1 model, which was raise higher and given more vision blocks compared to the M1 cupola on the earlier M48 tanks.
That's an M48. You can easily tell it apart from the similar looking M60A1 by comparing the frontal hull. The M48's is more rounded while the M60 series has two flat angled plates.
