Gamera, you are correct. I had to look up the T-26, as you peaked my interest. Article states they were vulnerable to the PZKW III and IV, but most were lost due to mechanical breakdown, artillery, and especially air attacks. The main gun was 45 mm, and pretty good for the time.
The article did mention that the rivet construction led to issues where the rivets would pop when the tank was hit, and become projectiles inside the tank. The rivet seams were not well done, and the tank was vulnerable to Japanese anti-tank infantry carrying molotov cocktails. The burning fuel would get into the tank through the seams.
Thanks for peaking my interest. I learnt me something today.