Releases plenty of product for testing (4,6)

I believe the answer is:

free sample

'product for testing' is the definition.
(sample of a product)

'releases plenty' is the wordplay.
'releases' becomes 'frees' ('free' can be a synonym of 'release').
'plenty' becomes 'ample' (I've seen this in another clue).
'frees'+'ample'='FREE SAMPLE'

'of' acts as a link.

(Another definition for free sample that I've seen is " small PR gift?".)

I've seen this clue in The Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.