Slender Squirrel

I removed the 4th squirrel and made it a separate spotting as the other 3 are Slender Squirrel but that one was a different animal in the same area and appears much darker although that could be due to poor light.

Hanna, there are 34 species of squirrel in Borneo and none of them are the same species as the Common Squirrel which lives in your part of the world although many of them look similar. It is most likely a Kinabalu Squirrel but it will need more research to confirm it.