---
product_id: 303302457
title: "3877 7-Way By-Pass Relay Buzzer and Smart Chip"
brand: "maypole"
price: "₨21878"
currency: LKR
in_stock: true
category: "Maypole"
url: https://www.desertcart.lk/products/303302457-3877-7-way-by-pass-relay-buzzer-and-smart-chip
store_origin: LK
region: Sri Lanka
---

# 12V smart chip power Audible buzzer alert Screw mount secure fit 3877 7-Way By-Pass Relay Buzzer and Smart Chip

**Brand:** maypole
**Price:** ₨21878
**Availability:** ✅ In Stock

## Summary

> 🔌 Tow Smarter, Tow Safer – The Ultimate 7-Way Bypass Relay for Pros on the Move

## Quick Answers

- **What is this?** 3877 7-Way By-Pass Relay Buzzer and Smart Chip by maypole
- **How much does it cost?** ₨21878 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.lk](https://www.desertcart.lk/products/303302457-3877-7-way-by-pass-relay-buzzer-and-smart-chip)

## Best For

- maypole enthusiasts

## Why This Product

- Trusted maypole brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Fully E Approved:** Drive with confidence knowing your trailer wiring meets UK safety and legal standards.
- • **Smart 7-Way Relay:** Seamlessly integrates trailer electrics with your vehicle’s 12V system for flawless towing.
- • **Audible Buzzer Alert:** Stay informed on connection status with a built-in buzzer that prevents costly wiring errors.
- • **Screw Mount Stability:** Easy and secure installation with robust screw mounting for vibration-resistant setup.
- • **Brass Contact Durability:** Premium brass contacts ensure reliable 15A current flow and long-lasting performance.

## Overview

The Maypole 3877 7-Way By-Pass Relay Buzzer and Smart Chip is a 12V automatic relay designed for trailer and caravan electrical systems. Featuring durable brass contacts rated at 15 amps, a secure screw mount installation, and an audible buzzer for connection alerts, this fully E approved device ensures safe, legal, and hassle-free towing. Trusted UK-made quality from Maypole, a leader with over 40 years of expertise in towing solutions.

## Description

So you have a trailer to tow, how do you connect it up to your vehicles electrics? Whether you need to tow for work or pleasure you will need to make your trailer safe and legal before you hit the road and Maypole has the answer with its range of towing leads and adaptors. This 7 Way By-pass Relay from Maypole is designed for use with electrical systems on caravans and trailers. It is an audible smart chip relay that runs on 12v electrics. Easy to use and fit this relay comes with full detailed instructions and is fully E approved. Maypole are the UK's leading manufacturer of high quality towing, trailer and related leisure products. Based in Birmingham with over 40 years of experience, they are a trusted and well-known brand for their products. With over 2000 lines currently, Maypole is using their knowledge and expertise in making new and innovative products and solutions which are helping their customers. From electrical cabling, to electrical winches, and even ice scrapper, Maypole has tried to cater for the Travel and leisure markets in the UK.

## Features

- Contact material: Brass
- Contact type: 7p7t
- Mounting type: Screw Mount
- 7-Way

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B003H5FX6Q |
| Brand | Maypole |
| Brand Name | Maypole |
| Coil Voltage | 12 Volts |
| Connector Type | Through Hole |
| Connector type | Through Hole |
| Contact Current Rating | 15 Amps |
| Contact Material | Brass |
| Contact Type | 7p7t |
| Contact material | Brass |
| Contact type | 7p7t |
| Current Rating | 15 Amps |
| Current rating | 15 Amps |
| Global Trade Identification Number | 05013008038772 |
| Item Type Name | Maypole 3877A 7-Way By-Pass Relay Buzzer and Smart Chip |
| Item Weight | 125 Grams |
| Manufacturer | Maypole Limited |
| Model | 3877 |
| Mounting Type | Screw Mount |
| Mounting type | Screw Mount |
| Operation Mode | Automatic |
| Part Number | 3877 |
| Wattage | 16.4 watts |

## Product Details

- **Connector type:** Through Hole
- **Contact material:** Brass
- **Contact type:** 7p7t
- **Current rating:** 15 Amps
- **Mounting type:** Screw Mount

## Images

![3877 7-Way By-Pass Relay Buzzer and Smart Chip - Image 1](https://m.media-amazon.com/images/I/614z5+2QwfL.jpg)

## Frequently Bought Together

- Maypole 12V 7 Way Bypass Relay with Audible Buzzer Trailer and Caravan Towing Electrics in Display Packaging, Black
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**Shop now:** [https://www.desertcart.lk/products/303302457-3877-7-way-by-pass-relay-buzzer-and-smart-chip](https://www.desertcart.lk/products/303302457-3877-7-way-by-pass-relay-buzzer-and-smart-chip)

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*Product available on Desertcart Sri Lanka*
*Store origin: LK*
*Last updated: 2026-07-30*