This month's ranking
Pressurize the system when mains water pressure isn't enough.
This is a drainage/removal pump (built to empty pools, basements, or wells), not a constant-pressure pump for sprinklers. It works well for lifting water from a cistern or well into the rest of the system, but if you need steady, sustained pressure for several sprinklers running at once, the surface pump below is better suited for that.
A centrifugal/jet surface pump, self-priming with a cast-iron body, specifically marketed for lawn sprinklers and garden irrigation — unlike the submersible pump above, it's built to deliver constant pressure, not just move water from one point to another. It's noticeably more expensive; it makes sense if your system genuinely needs extra pressure (check your mains pressure first before investing here).
A diaphragm pump (not centrifugal like the surface pump in this ranking) — it starts and stops on its own via a built-in pressure switch, on demand. Unlike the submersible (drainage) and self-priming surface pump (constant pressure for multiple sprinklers), this is a lightweight, portable booster for a single hose or low-pressure watering point: 4.0 GPM, 50 PSI, 110V AC. It includes garden hose adapters.