GKN screws*** ... Don't mention GKN screws to me, I'm sick of them! I have screwed in over a million self-tapping 'one inch 6' GKN screws ...
I spent 5 years in a labouring job, and for 3 of those years I was screwing metal brackets to wooden floor panels. (They said that my grammar school education was wasted ...!

)
There were 4 brackets per panel, but another labourer worked the opposite half of each panel, so I would do 2 brackets, 2 screws per bracket. 4 screws per panel, an average of (say) 400 panels a day, a 5.5 day week, 4 weeks off a year. 4 x 400 x 5.5 x 48 x 3 = 1,276,200 ... Blimey, more than one and a quarter million of the damn things!
In the end, my head couldn't take it any longer so I legged it and did a degree in Electronic Engineering instead!
*** They were very good screws! We used high-torque pneumatic screwdrivers to get the screws in quickly. With GKN screws you could give a full blast on the trigger and the screw would tighten and then stall the screwdriver. Every now and then, the management would try to save money by buying cheaper screws from '
Craptastic Ltd'. We'd snap the heads off hundreds of those every day until the bosses saw sense and chucked away the dodgy screws and shipped in more GKNs.