The GP189 battery is an alkaline button cell battery.
Each manufacturer can have a different part numbering system and so the 189 button battery is also known as GP189 LR54 AG10 G10A L1130 LR1130.
Manufactured by GP Batteries, the 189 is an alkaline button cell battery and made very popular by small electronic equipment including calculators and electronic games.
This pack contains 5 batteries.
I have been using this pump all summer to keep my boat, lawn tractor and a whole bunch of other stuff filled up around here. I still use 5 gallon containers for their portability and even with 10 of those I'll have to fill them twice to get through the summer. This pump has been great for my needs. If you are sick and tired of having to hold a 5 gallon container of fuel in the air while attempting to get those funky nozzles to work, buy this pump.
So far it’s working as well as I had hoped. Nothing is perfect when trying to transfer gas, but this does a very decent job. You need to make sure to lift the nozzle and hose up at the end of the fuel transfer to allow any residual fuel to run back into the tank or it will dribble out all over. It empties most of a five gallon gas can in a couple minutes without having to lift and hold the can up which is exactly what I wanted.