Exterior Components› Body Panels and Components

Master Lock

TRAILER ALARM SYSTEM

$86.02

SKU: M014 4840DATSEN

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Special Order
Ships in 4–6 weeks
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Beginner — under 30 min

Description

The Master Lock 4840DATSEN Trailer Sentry is a boat trailer anti-theft alarm system. It provides electronic security with a 110-decibel alarm siren that sounds when the trailer wiring is disconnected. This system also acts as a power module, drawing power directly from the vehicle's battery to the trailer.

The alarm can be mounted under the hood, and the power module is installed under the vehicle with a voltage sensor to prevent battery drain and detect whether lights are functioning. The anti-theft feature is completely submersible, and trailer lights can be disconnected remotely while the trailer is in water.

Fitment

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Available on iOS & Android

Specifications

BrandMaster Lock
Part NumberM014 4840DATSEN

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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