Finding total quantities in multiple lines of data

Good day all - Happy New Year!

Attached is an extract from historical data sheet. Actual version runs to 34,000 lines!

You will see quantity figures in column E and Product Code in Column F. I need to work the formula to give me a total per product code. So you can see that in Column F "KZC" occurs twice, so that the total for that piece would = 4.

Any pointers gratefully received.

Cheers!
Rob P