Laing Circulating Pump

The water heater that I was inspecting yesterday had a Laing Circulating pump attached to the bottom of the tank and feeds back up into the house. I have not seen this before. I have tried doing research on it and I beleive it is for getting the hot water where it is needed quicker but am not sure. Could it be that the heater is in the basement and the foundation walls are 12’ high so it needs a pump to circulate the water.

Any info or a link would be great. One other question is what should I be looking for when inspecting this.

Hope that was on the return line. Works better that way.