Magnetic plug v. Drain on a suction diffuser

steamfitter

I was always intrigued by the 3/4" steel plug on the bottom of a suction diffuser. I believe I read somewhere that it is more tionally magnetic to capture very fine ferrous particles in the water inlet to a centrifugal pump.
There is the drain that poses an issue. The outlet on the bottom is a perfect location for a drain valve. So what do you do with the magnetic plug that comes with the suction diffuser if you use that outlet for a drain?
I often thought, why didn't the manufacturer place two outlets on the bottom of this unique device? One for the drain and the other the magnet.

ScottSecor

We always left them in place if they were actually a magnet. However, I'm not sure all brands of suction diffusers come with a magnetic plug, been a long time since we installed end suction base mounted pumps.