What's to say?  It's not very large.  It works perfect in my 2003 Chevy truck to add a Fuel Additive into the fuel tank!!!  It should work for Power steering and transmission also, at least on Car/trucks that's not hard to get to or down load were access is bad.  The design helps keep you from spilling when your poring a fluid into it!  For under $5, not a bad deal.  Hang it up out of the way when done with it.  It's able to fit into your Transmission Dip Stick tube, so it has to be small enough, so you can just dump a bunch a fluid into it at once!!!  It's small and doesn't hold all that much.  For what it is, I like it.