Purchased two of these to update two of my current bilge pumps. Very easy to swap out with my existing Rule 1500 pumps. The pump comes with several different switch mounting positions. Which makes getting a good trigger level much easier than a float. The pump comes with a check "flap" that sandwiches in between a washer and the output fitting. Tip: when you tightening the fitting it will spin the flap hinge point. So, set the hinge point at the 9 o'clock position and when you tighten it will spin up to the 12 o'clock position. Which is where you want it. That way the flap is hanging down instead of to the side or hinging at the bottom.Construction wise, this feels like a solid piece of tech. It weighs in at least twice as much as the Rule pump. It is also much larger. Think a little larger in height and diameter than a quart sized paint can. The switch is roughly the size of a deck of playing cards. Wiring is a direct swap for what you most likely have now.Couple things I found out when changing out pumps. The surveyor recommended up sizing the pumps because the gph combined didn't meet AYBC recommendations. Turns out the manufacturer of our boat installed 5 amp breakers on all of the bilge pumps. Which was 10 amps too small for the Rule 2000 pumps that they installed. A prior owner downsized the pumps to Rule 1500 (dumb) instead of figuring out what was going on. I didn't realize any of this until I went to replace the pumps and they kept blowing the breakers. These Johnsons rated to run at 7 amps. But, I'm guessing they drawl a little more at start up. You'll want to make sure that your breakers and wiring are the correct size. The Rule 1500 is a 7 amp pump too. So, it was a miracle that they ran at all. Good thing they were never really put to the test.Anyway, crisis averted and we're all done up nice now.For the price, quality measured in heft, mounting options and no float switch these pumps are a gimme.Mike from the lifesaport blog