Four Contact Plug Key

Last updated: September 2026

Quick Answer: The Four Contact Plug Key is a multi-point physics laboratory key that lets students make, break or select between several circuit connections using removable conductive plugs across four contact positions. It is used where an experiment needs more than one switching point – for example selecting between different resistors, cells or circuit branches in current electricity and bridge-type investigations. LabEquip supplies this key as part of its Keys and Switches range for schools, colleges and technical laboratories.

Product Description

This Four Contact Plug Key from LabEquip extends the standard single plug-key principle to four separate contact positions mounted on one base. Inserting a conductive plug into a given position completes the circuit at that point, while removing it isolates that path, so a single key can control or select between multiple connections without students having to rewire the whole circuit each time.

This makes it useful in practicals that compare several resistances, switch between measuring instruments, or need more than one make/break point along a circuit – common in current electricity, resistance and bridge-method experiments where a student needs to isolate one section of the circuit while keeping others connected.

The exact terminal layout, plug material, base construction and voltage/current rating were not included in the specification on file for this listing. Institutions who need the precise configuration before finalising a lab equipment order are welcome to confirm details with LabEquip.

What This Key Helps Students Learn

• How a multi-contact plug key lets one accessory control several circuit connections.
• How to selectively open or close individual paths in a circuit using separate plug positions.
• Why isolating one part of a circuit while keeping another connected is useful when comparing components.
• How to read a circuit diagram that shows multiple plug-key positions.
• The difference between a single-circuit key and a multi-contact key in terms of what each can control.

Specifications

Safety Note

Use this key only within its confirmed voltage and current rating, and treat it as a low-voltage educational accessory unless LabEquip explicitly confirms a higher rating for a specific order. Do not touch exposed terminals or plugs while any part of the circuit is energised, and always open the relevant plug position before rewiring that section. Recommended for classroom and laboratory use under teacher or instructor supervision.

Care & Maintenance

• Keep all four contact positions and plugs clean, dry and free of corrosion.
• Insert and remove each plug gently, without forcing it into the wrong position.
• Inspect terminals and contact blocks for looseness or damage before each practical session.
• Store the key with all its plugs together in a dry laboratory cabinet so none are misplaced.

Why Choose LabEquip

LabEquip supplies physics lab keys, switches and current-electricity apparatus to schools, colleges and technical institutes across India. Alongside this Four Contact Plug Key, our Keys and Switches range includes the simpler Single Circuit Plug Key and the Reversing Key Commutator for direction-reversing circuit work.

Frequently Asked Questions

What does “four contact” mean on this plug key?
It refers to four separate positions on the same base where a conductive plug can be inserted to make or break a connection, letting one key control multiple circuit points.

Can I use just one of the four positions at a time?
Yes, each position works independently, so you can insert or remove plugs at individual positions as your circuit requires.

What voltage or current rating does this key support?
The exact rating was not confirmed for this listing. Treat it as a low-voltage educational accessory and contact LabEquip for a specific technical rating before ordering.

How is this different from a single circuit plug key?
A single circuit plug key has one make/break point, while this key gives four, so it can control or select between several connections without rewiring.

Is this key suitable for bridge-method experiments?
It is commonly used in circuits that need more than one switching point, which includes many bridge-type and resistance-comparison setups, subject to your specific circuit design.