Rule RM1100B, Auto Submersible Bilge Pumps 12V 1100 GPH AutoSense
- 1100 GPH rated flow, listed as 18.33 gpm
- 1 meter maximum lifting height
- 12 volt corded electric pump
- Switches on at 2 inches of water, off at 3/8 inch
- Thermal cut-off and backflow prevention
- Body 6.75 x 8.5 x 3.5 inches, 1.2 pounds
Last refreshed Oct 2, 2026 · Based on the Amazon listing and published specifications, not hands-on testing.
A compact automatic bilge pump with the highest flow in the Rule-Mate range, suited to boats that take on more water. Install details such as hose size are not given in the listing.
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ASIN: B07L3K5VMPModel: RM1100BCategory: Bilge Pumps
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Overview
Not a pump you switch on by hand, the RM1100B is a submersible unit that senses water in the bilge and runs on its own. A threaded discharge connects the outlet, and hidden air vents clear airlocks.
Rule-Mate raised flow over earlier versions without raising the power draw, which suits an electrical system with little spare capacity. Thermal protection and backflow prevention add to the case for fitting it and forgetting it. The limitation is the modest lifting height and an unstated hose size.
Who it's for
Cruisers and day boats where a bigger bilge needs automatic cover while docked or underway. Owners with a tall discharge run, or anyone who wants a manual override switch, should check other pumps.
Pros and cons
- Largest flow size in the range
- Automatic level sensing
- Backup cycle if sensor blocked
- Thermal cut-off against overheating
- Lifting height is only one meter
- Hose or fitting size unstated
- No manual switch described
Performance notes
Flow rate sets how quickly the bilge empties, and lifting height limits how far above the pump the water can be pushed. The sensor starts the pump at a set depth and stops it near the floor, with a timed backup cycle if the sensor is blocked. Backflow prevention stops water draining back into the bilge when the pump stops.
Specifications
| Brand | Rule |
|---|---|
| Model | RM1100B |
| Dimensions & fit | |
| Item Dimensions L x W x H | 6.75 x 8.5 x 3.5 inches |
| Maximum Lifting Height | 1 meter |
| Weight | 1.2 pounds |
| Capacity & performance | |
| Flow Rate | 18.33 gpm (1100 GPH) |
| Power & efficiency | |
| Power Source | Corded electric |
| Voltage | 12 volts |
| Construction & materials | |
| Material Type | Plastic |
| Color | White |
| Warranty & support | |
| Manufacturer Warranty Description | Manufacturer warranty |
Closest rivals on specs
SEAFLO 06 Series Automatic Submersible Bilge Pump- Flow Rate 18.33 vs 12.5 gpm (+47%)
Attwood WaterBuster Portable Submersible Pump- Flow Rate 18.33 vs 3.33 gpm (+450%)
Frequently asked questions
How does the RM1100B turn on?
Auto Sense Intelligence activates the pump when water reaches 2 inches and shuts it off at 3/8 inch. A backup cycle runs every 2.5 minutes if the sensor is blocked.
Is the RM1100B a hand pump or a manual switch unit?
No. It is an automatic submersible pump, and the listing mentions no manual switch or float switch.