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Resistance Manufacturer, Suppliers and Exporter in India

School Instrument India is leading Resistance Manufacturer,and supplier and Exporter in India, Algeria (Algiers), Angola (Luanda), Argentina (Buenos Aires), Armenia (Yerevan), Australia(Canberra), Austria (Vienna), Bahrain (Manama), Bangladesh (Dhaka), Bhutan (Thimphu), Bolivia (Sucre), Botswana (Gaborone), Brazil (Brasília), Brunei (Bandar Seri Begawan), Montenegro (Podgorica), Morocco (Rabat), Mozambique (Maputo), Myanmar (Naypyidaw), Namibia (Windhoek), Nepal (Kathmandu), New Zealand (Wellington), Nigeria (Abuja), Oman (Muscat), Palestine (Ramallah), Panama (Panama City), Papua New Guinea (Port Moresby), Paraguay (Asunción), Peru (Lima), Philippines (Manila)¸ Portugal (Lisbon), Qatar (Doha), Rwanda (Kigali), Saudi Arabia (Riyadh), Senegal (Dakar), Serbia (Belgrade), Sierra Leone (Freetown), Slovakia (Bratislava), South Africa (Cape Town) (Pretoria) (Bloemfontein), South Sudan (Juba), Spain (Madrid), Sri Lanka (Sri Jayawardenepura Kotte) (Colombo), Sudan (Khartoum), Syria (Damascus), Tanzania (Dodoma), Thailand (Bangkok), Togo (Lomé), Tonga (Nuku'alofa), Trinidad and Tobago (Port of Spain), Tunisia (Tunis), Turkey (Ankara), Turkmenistan (Ashgabat), Uganda (Kampala), United Arab Emirates (Abu Dhabi), United Kingdom (London), United States (Washington, D.C.)

Written by Palak Mall, Senior Content Writer · reviewed by Arvind Kumar, Lab Equipment Specialist, 12+ years in laboratory supply · updated 17 October 2026

Resistance lists 13 items for measuring and controlling resistance in school and college physics labs: metre bridges, post office boxes and a single-wire potentiometer, plug-type resistance boxes, resistance units and a rheostat, and a platinum resistance thermometer and a thermistor for temperature work. Accuracies and sizes are those given in each listing.

Bridges and the potentiometer

Instrument	What the listing specifies
Wheatstone Bridge, 4 Gaps	Four-gap bridge with broad, heavily plated brass strips; 24 SWG bare constantan wire over a metre scale in millimetres, clamped at the ends to keep end errors negligible; 4 mm socket terminals; removable brass gap strips; replaceable wire; jockey supplied
Wheatstone Bridge, 2 Gaps	Two-gap bridge: 24 SWG constantan wire on a metre scale, stout plated brass end plates, and a brass strip with 4 mm sockets along the back; jockey supplied
Potentiometer, Single Wire	One-metre, 24 SWG bare constantan wire on a scale in centimetres and millimetres, clamped at the exact ends of the scale; heavy-duty 4 mm sockets on a long baseboard
Post Office Box, Wheatstone Bridge	Decade dial type with non-inductively wound, double-silk-covered coils; two enclosed tapping keys for battery and galvanometer; unit coils accurate to ±0.1 per cent
Post Office Box, Plug Type	Plug type in a polished teak box with a hinged lid; ratio arms and resistance arms of 16 coils from 1 to 50000 ohms with an infinity plug; two spring keys for battery and galvanometer; Bakelite panel lined in white to show the circuit
Spare Jockey	Insulated handle, plated brass contact and terminal with a 4 mm socket; about 90 mm long

Resistance boxes, units and rheostat

Item	What the listing specifies
Resistance Box Plug Type (Manganin)	12 coils of double-silk-covered manganin wire, 13 plugs, 12 mm thick brass block; ±0.05 per cent
Resistance Box Plug Type (Constantan)	12 coils of double-covered Eureka constantan on Bakelite spools, 13 plugs, 12 mm brass block, in a teak box; non-inductive; ±0.1 per cent
Resistance Coils	Resistance units with high-stability metal film elements; ±1 per cent
Rheostat	Air-cooled sliding rheostat: oxidised constantan wire on a vitreous enamelled steel tube, die-cast end stands, nickel-plated multi-leaf phosphor bronze slider; 4 mm terminals; tube 200 to 400 mm long and 43 mm in diameter

The two plug-type boxes differ in wire and accuracy. The manganin box is listed at ±0.05 per cent, and the constantan box at ±0.1 per cent in a teak case. For general circuit work, the metal film resistance units at ±1 per cent are the economical choice, and the rheostat varies the current continuously.

Resistance that changes with temperature

Resistance Thermometer, Platinum: fine platinum wire wound non-inductively on a mica frame, with a pair of compensating leads and four 4 mm terminals, sealed in a borosilicate tube; for use up to 150 °C with a bridge such as the Carey Foster bridge.
Thermistor Demo: an NTC thermistor with a nominal resistance of 4.7 kilohm in a glass tube, with 4 mm sockets.

The two make a useful contrast: the platinum element’s resistance rises with temperature, while the NTC thermistor’s falls.

Also listed here

The Supplementary Transformer Coils are coils about 100 x 53 x 28 mm with 4 mm sockets that fit a double core to make a low-voltage AC transformer, or serve as an electromagnet on half a core. They are supplied in different combinations.

Related ranges

This range is part of Electricity & Magnetism. Galvanometers for the bridges are under Meter and Radiations, manganin and constantan wire, keys and leads under Compasses and Components, and capacitance and inductance boxes under Circuit.

Questions buyers ask

What is the difference between the two metre bridges?
The number of gaps. The Wheatstone Bridge, 4 Gaps has four gaps closed by removable brass strips, and the Wheatstone Bridge, 2 Gaps has a two-gap strip for normal Wheatstone bridge work. Both use 24 SWG constantan wire on a metre scale and come with a jockey.

Which resistance box is the most accurate?
The Resistance Box Plug Type (Manganin), listed at ±0.05 per cent, against ±0.1 per cent for the constantan box.

What temperature range does the platinum resistance thermometer cover?
It is listed as suitable for low-temperature work up to 150 °C only, because its connections are soft soldered.

Is a jockey supplied with the bridges?
Yes, each metre bridge comes with one. The Spare Jockey is listed separately for bridge and potentiometer work.

Request a quotation

Send the item names and quantities through the contact page, with the rheostat tube length wanted and the coil combination for the supplementary transformer coils.