Overview

The Attwood Marine 4201-7 is an automatic float switch with cover for 12V and 24V bilge pump systems. It adds automatic on and off control to a non-automatic electric bilge pump and is rated for loads up to 12 amps at 12V DC or 6 amps at 24V DC. The switch trips the pump at a 2 inch water level, which gives the bilge a prompt response without needing manual activation.

The covered low-profile body suits tight bilge spaces where sloshing water and loose debris can cause trouble for exposed switches. It mounts on surfaces from horizontal up to 24 degrees, uses 36 inch wire leads for installation, and includes a test knob so pump operation can be checked at the switch. The sealed switch body is mercury-free and CE rated.

Key features

• Converts a manual bilge pump setup to automatic operation on 12V or 24V DC systems
• Handles pump loads up to 12 amps at 12V DC or 6 amps at 24V DC
• Mechanical float switch turns the pump on at 2 inches of water
• Covered housing helps cut down cycling from bilge slosh and keeps debris away from the float
• Low-profile body mounts on surfaces from horizontal up to 24 degrees
• 36 inch wire leads give extra reach for routing in the bilge
• Built-in test knob lets you check pump operation without lifting the float by hand
• Sealed switch body resists moisture, fume ignition, and electrical shock

Installation and setup

This switch can be mounted on its own in the bilge or fitted directly onto the rear slots of an Attwood V-Series pump bracket. That gives a cleaner install when you are pairing it with a compatible pump bracket and helps in compartments where space is limited.

For retrofit work, the current rating is the first thing to confirm before purchase. The switch needs to be matched to a pump that stays within the stated 12V or 24V load limits, and the mounting surface needs to let the float move freely without hoses, wiring, or hull structure getting in the way.

Compatibility and fit

This model is a good match for boats using a separate bilge pump and switch arrangement rather than an integrated automatic pump. It fits many small to mid-size bilge compartments where a covered switch is preferred to help control nuisance cycling and keep debris from interfering with float movement.

It also makes sense when you want a simple mechanical switch with a local test point at the bilge. That can be useful on fishing boats, runabouts, small cruisers, and sailboats where routine pump checks are part of normal maintenance.