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ISS Keyring Calibration Card Tester Check

The ISS Calibration Card, check your equipment is within range using a precisely defined set of values printed in to this handy card. It even doubles as a key ring so it's always ready to use.

Next Day Delivery (subject to availability)

£19.95 exc. VAT £23.94 inc. VAT £36.00 inc. VAT
  • Compatible with all installation and PAT testers
  • Earth Continuity Verification
  • Insulation Resistance Verification
  • 5 Calibration Points
  • FreeDelivery
  • 30DayMoneyBack
  • Description
  • Resources
  • Delivery

The ISS Calibration Check Card


Does the calibration of YOUR meter check out?

A verification unit is a necessary tool required by all tradesman working with electrics both in domestic and commercial environments.

The CalCard verification unit utilises a specific fixed range of resistance values, through which the ongoing accuracy and operation of test instruments between calibration periods can be verified.

This verification process is one of the mandatory requirements for meeting acceptable standards for all tradesman working in electrical environments. In the UK it is deemed one of the requirements to demonstrate “competence” of the tradesman by all inspectorates and the Health and Safety Executive.

What makes the national award winning CalCard the most popular choice with tradesmen and inspectorates is not just its size and affordability, but more importantly the ability to verify both the instrument and probes together.

The CalCard is one of the most affordable pieces of test equipment to meet compliance requirements.


*If you've already purchased your Cal Card and you're looking for our easy to follow setup guide, please click the image below.


Cal Card Setup


Once you've set up your CalCard, you can grab our handy CalCard Record Sheet and RCD Record Sheet to log your recordings.


Cal Card Record Sheet            RCD Record Sheet


What has made the CalCard the most popular choice for Electricians?

The CalCard satisfies all appointed inspectorates, British and European standards and HSE requirements with regard to instrument continuity and insulation verification, reflected in the recommendations from all inspectorates and governing bodies.

There are over 15,000 CalCards in use in the UK by End Users, Suppliers, Distributors, Training and Calibration Companies.

This successful and innovative product when first introduced presented a new radical approach to the then large and expensive “Box” solutions. However after winning three national major electrical awards, followed by ELECSA and NICEIC endorsement with re-badging the CalCard has gained an excellent unchallenged reputation.

Simply search CalCard Forum to read some of the independent reviews.


Handy & Compact

Yes it really is credit card sized but more robust and not as flimsy. Manufactured in a tough resilient very strong multi-layered glass fibre construction 1.6mm thick. Incorporating a hole for the included key ring.

  • Small enough to be stored with the instrument or even in your wallet.
  • There when you need it
  • Not lost in a toolbox or van
  • Built tough for the engineering environment
  • Integral Keyring for attachment to the instrument?

Improved Design

Test instrument contact is made through specifically constructed gold plated recessed touch pads.

Other Checkboxes and verification tools incorporate 4mm sockets, these not only limit the range of instrument but also require the removal of the instrument probes and clips to enable testing.

The CalCard works with all instruments and with whatever probes are connected to the instrument.

  • Verified measurements include the instrument probes
  • Recessed pads enable probe location
  • Reliable, quick and repeatable
  • Universal interface for all makes of instrument
  • CalCard is the only checkbox that verifies the instrument and the probes together

An integral part of compliance is that users record their periodical measurements against an identifiable check source. These records then demonstrate to an inspector that users are performing the verification task.

This operation is simplified on the CalCard by the inclusion of an identification serial number and provision of base value recording grid on the rear of the CalCard.

These are then sealed with a protective covering providing an indelible record for inspectorates.

  • Convenience for comparisons
  • Traceable reference standards
  • Indelible for inspector’s authentication
  • Free downloadable record sheets*

    *Please see our Resources section 

The Cal Card is Recommended/Endorsed by the following industy bodies


Endorsements Complete




Orders requiring calibration 

Whilst we take the greatest care to get all orders dispatched and delivered to you in the stated time frame, orders received PM and requiring
calibration may on occasion miss dispatch that day, according to the complexity of the calibration. Be assured they will ship on the next dispatch
this in most cases should not add more than 24 hours to your delivery.

Bank/Public Holidays

Predicted delivery times are based on regular trading days Monday to Friday. Public holidays, bank holidays and weekends are outside the usual scope 
of our dispatch and subject to activities/holidays of our carriers and therefore may incur additional days lead time to your order.

*UK Mainland (Temporarily revised June 2020)

Please note that regrettably, we have had to realign our delivery service options to those available from our carriers.
During the current situation surrounding the effects of the Coronavirus pandemic, logistics from every company are under immense pressure to deliver goods on time.
We have taken the decision to temporarily limit our services rather than let our customers down.
We hope you will understand our position on this and we apologise unreservedly for the inconvenience we know this will cause.
We look forward to restoring our full delivery service schedule just as soon as we are able.

Standard FREE 1-2 Day Courier Delivery – UK Mainland only - Zones A & B

Included in the price for all orders over £75.00 (exc vat). Sent using express courier, delivered within 1-2 working days from the date of your order, subject to availability.


Next Day Anytime Delivery (Excluding Saturday & Sunday) – UK Mainland only - Zones A & B
Sent by express courier, delivered next day (excluding weekends) from the date of your order, subject to availability.


Orders must be placed before 3:00pm for a qualifying next day delivery and a telephone number supplied, subject to availability.

New Postage Map Sept 2018>

Delivery Surcharges

Because of the high cost of carriage, we need to apply a surcharge on all deliveries made in the following regions bringing the carriage charges to:

  • Zones A & B  - Mainland delivery rates apply. 
  • Zone C - Scottish Highlands (Charges are calculated at the checkout).
  • Zone D - Outer Hebrides, Orkney Isles, Shetland Isles, Isle of Man, Scilly Isles, and Channel Islands (Charges are calculated at the checkout).
  • Zone E - Northern Ireland (Charges are calculated at the checkout).
  • Zone F - Republic of Ireland (Charges are calculated at the checkout).

Offshore Services

All offshore deliveries are a 2 day service as standard. This includes Channel Islands, Northern & Southern Ireland, Scottish Islands, Isle of Man and the Scilly Isles.

International Delivery

International delivery charges are automatically added to your order at the checkout. For any questions regarding international deliveries please contact us at


All export inquiries should be directed to the export division before placement of order.

If no shipping option is available to your selected country please call us FREE on 0800 0224 060 to purchase your items.
All stated prices are subject to VAT at the current rate where applicable E&OA