In article ,
Jeff Layman wrote:
I am replacing some old wall lights with some new Där fittings. I was
somewhat surprised to see that the wallplugs and screws supplied were of
different lengths. The wallplugs were 25mm x 5mm, and the screws 35mm x
3.5mm. The diameters match well, but why would you use a 35mm screw with
a 25mm wallplug?

You recess the plug into the wall so that it is not putting any strain on
the plaster.

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle