Hello,
It is a filler primer, but it is called Spray Putty.
Bright Orange in colour, looks like paint with Talcum Powder added, very easy to spray on a 1mm thick coat, dries quickly.
Dont know why it is called "Putty" nothing like the putty used in fitting windows.
Very quick to rub down when dry, will shine when rubbed with a cloth!.
Photos on my website of the hull with grey primer on it, that was hard, slow work - - very thin coats each time.
Enjoyed the Spray Putty so much I finished the hull - - - and no photos !!!.
John.