Brass Two Way Plug Key Switch

Product Code : SCL-EAE-12121

Brass Two Way Plug Key Switch (SKU SCL-EAE-12121) is a three-block plug key that sends current through either of two circuit branches from one common input, depending on which gap holds the plug. It is a familiar part of Class 12 and B.Sc. potentiometer practicals, for instance when comparing two cells. Science Lab Supplies manufactures this key in its Saha unit at Plot 448, HSIIDC Industrial Area, Ambala, India, and offers it at factory level to schools, colleges, tender contractors and distributors.

Specifications

Each specification has its own row in the table below. In short, three solid brass blocks sit in a line on a heavy insulated polymer base, forming two gaps around a shared central block, with one tapered brass plug on an insulated handle and three heavy brass binding posts, rated at 24 V AC/DC and 5 A.

Applications and Experiments for the Two Way Plug Key

The incoming lead goes to the central block and the two branches to the outer posts. Putting the plug in the left gap completes one branch, moving it to the right gap completes the other, and removing it opens both, so one circuit can switch between two sources or loads in seconds.

• Class 12 physics: comparing the EMFs of two primary cells on the Potentiometer with Jockey Pencil.
• B.Sc. potentiometer work with a complete Potentiometer Kit, switching between cells or reference sources.
• Bringing a protective resistance or a sensitive meter in or out of a circuit.
• Directing current through two alternative experimental loops in electricity practicals.

Use the key on low-voltage supplies below 24 V only, and keep its plug with the same base so the tapered fit stays tight.

Standard Scope of Supply

You receive one Brass Two Way Plug Key Switch base assembly with three binding posts, one precision-machined brass plug with a non-conductive handle, and a schematic guide sheet detailing the alternative wiring options. Cells, leads and potentiometers are separate and can be quoted together with it.

Packing, MOQ and Lead Time

A price can be requested for one key or for a batch sized to your potentiometer and bridge benches. The quotation confirms packing, delivery time and price for that number, and you can list jockeys, other keys or galvanometers on the same request to equip the benches in one go.

Using its Importer-Exporter Code, Science Lab Supplies can ship to buyers in Iraq, Nigeria, Kenya, Ghana, Ethiopia and Tanzania. Get in touch from the contact page, add the key to the enquiry cart, or check the lab tender page if you are preparing a tender.

Frequently Asked Questions

Why does the key have three brass blocks?
The three blocks create two gaps that share a central block. The input connects to the centre and each outer block feeds one branch, which gives the two-way choice from a single plug.

How are both branches switched off?
Pull the brass plug out of the base completely. With neither gap bridged, both output channels are open and no current flows through either branch until the plug is inserted again.

Can it be connected to 220 V mains?
No. The key is designed for low-voltage educational circuits up to 24 V AC or DC with a maximum of 5 A, and must never be wired to household mains or other high-voltage supplies.

Is Science Lab Supplies the manufacturer or a trader?
Science Lab Supplies is the maker of this key, producing it at its factory in Saha, Ambala, India. Quotations therefore come from the manufacturer itself, not from a stockist or trading firm.

Related Keys, Jockeys and Potentiometer Items

These items appear in the same potentiometer, bridge and electricity practicals as the two-way key: other keys for making, pulsing or reversing current, a jockey for the bridge wire, and the rheostat and galvanometer that complete the circuit. All can be added to the same quotation.

• Brass One Way Plug Key — single-gap brass key to make or break one path.
• Brass Four Way Plug Key — four-block circular key with two plugs for reversing current.
• Reversing Key Commutator For Lab — lever commutator rated 24 V and 3 A.
• Tapping Key Physics Lab — momentary spring key for brief contacts.
• Pencil Jockey for lab — insulated knife-edge probe, about 100 mm long, with a 4 mm socket.
• Rheostat, Constantine (Eureka) Wire — usable as variable resistance or potential divider.
• Galvanometer — centre-zero meter reading −500–0–500 µA.

Browse the full Electrical and Electronics range, the Lab Meters range for galvanometers, or all physics lab equipment.

Last updated: 9 October 2026