Pulasam is also called Wild rambutan. It is a local fruits which can find in Malaysia. The outlooks is a bit like rambutan. But the skin is harder than rambutan. I do not know how is the tree look like, but i guess is similiar with Rambutan Trees.
Pulasam is a seasoning fruits. You can get it once a year in Malaysia. Due to the climate change in the world, you might able to get it twice a year. During the season period, you can get 3 kg for RM 10. It is really a good price. Sometimes, it is selling 1kg for RM 5. It is still worth to buy. As a local Malaysian, you should try this Pulasam.