Here's a height reference for the two of them I suppose. And Sheela in her work outfit. They're both mechanics, and Sheela has a hobby of invention. She's 5'1" and Flo is 2'3". Natural for the species'.

That's a welding mask on Floats' head.

These two are one of the best building teams in there era! :p

Floats © Jetslasher, Ottsels © Naughty Dog Games.
Sheela © me, Lombaxes © Insomniac Games.