BATTERY DOCTORAutomotive Toggle Switches

BATTERY DOCTOR SPST On/Off Toggle Switch with Blue LED

The BATTERY DOCTOR Automotive Toggle Switch (MPN 20521) is an SPST, On/Off switch with a silver actuator and black stem, featuring a blue LED. It offers 3 connections, 1/4 in male terminals, and panel-mount installation.

SKU 3G-OTH-516157

Brand

BATTERY DOCTOR

Item

SPST On/Off Toggle Switch with Blue LED

Local availability & support

Delivery: Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment: Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

BATTERY DOCTOR

Manufacturer Part Number

20521

Type

SPST, On/Off, Silver, Black 

Features

Blue LED 

Terminals

1/4 in Male 

Stem Color

Black 

Connections

3

Switch Type

Toggle Switch 

Contact Form

SPST 

Actuator Color

Silver 

Mounting Style

Panel Mount 

Switch Function

On/Off 

Technical Documents

No technical documents available for this product.

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BATTERY DOCTOR Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

Frequently Asked Questions

What is the BATTERY DOCTOR 20521 toggle switch used for?

The BATTERY DOCTOR 20521 is an SPST On/Off toggle switch with a blue LED, designed for automotive electrical circuits. It is commonly used to control accessories such as lights, fans, or pumps in vehicles, providing a reliable panel-mount switching solution.

What are the specifications of the BATTERY DOCTOR 20521 switch?

The BATTERY DOCTOR 20521 is an SPST toggle switch with On/Off function, silver actuator, black stem, and 3 connections. It features 1/4 in male terminals, a blue LED indicator, and panel-mount installation. The brand is BATTERY DOCTOR.

Where to buy the BATTERY DOCTOR 20521 toggle switch worldwide?

3G Electric supplies the BATTERY DOCTOR 20521 toggle switch to customers worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us to order this SPST On/Off switch with blue LED.

How to install the BATTERY DOCTOR 20521 panel-mount toggle switch?

To install the BATTERY DOCTOR 20521, drill a panel hole to the switch's specified diameter, insert the switch through the front, and secure it with the included mounting nut. Connect the 1/4 in male terminals to your circuit using female quick-disconnect connectors, ensuring proper polarity for the blue LED.

Used in

Common applications for BATTERY DOCTOR

Fleet maintenance — BATTERY DOCTOR 31200 Series circuit breakers for overcurrent protection in truck electrical systems

Automotive wiring harness repair — BATTERY DOCTOR GPT primary wires (20 AWG, 22 AWG) for replacing damaged low-voltage cables

Industrial control panels — BATTERY DOCTOR primary wires for internal wiring of 60 V control circuits

Marine battery systems — BATTERY DOCTOR circuit breakers for protecting DC circuits on boats

Off-road equipment — BATTERY DOCTOR 31200 Series breakers for resettable protection in ATVs and utility vehicles

Battery charger connections — BATTERY DOCTOR primary wires for extending charger leads in workshop environments

BATTERY DOCTOR Products

3G Electric supplies BATTERY DOCTOR automotive toggle switches. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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