ExLRT vs LRT: Size matters


Part one in our Loop Resistance Tester comparison series looks at the difference in the size & weight of the only two tools approved by The Boeing Company – the legacy ‘yellow box’ LRT and its newer counterpart, the ExLRT.

Lightening the load

Size matters, especially when you’re working at height or in small spaces. The ‘yellow box’ LRT loop tester (aka 906-10246-3) has been anecdotally blamed for back, neck and shoulder problems due to its weight.  The ageing design means its size isn’t suited to MRO field use, yet up until now it’s been the only Boeing-approved tool for loop and joint resistance testing.


The good news is, there’s a Boeing-approved loop tester that’s 82% lighter than the LRT.


The weight is over

The ExLRT weighs just 6.6lbs (3kg) versus the legacy LRT which is a whopping 37.5lbs (17kg).  The difference is the equivalent to 74 iPhones (or 140 croissants if you’re an Android user).  Believe us when we say you will really appreciate what a huge difference this is.

exlrt vs lrt weight difference

According to the World Health Organisation, musculoskeletal conditions are the leading contributor to disability worldwide, with low back pain being the single leading cause of disability in 160 countries. In the US alone, nearly 2 million workers suffer from work-related musculoskeletal disorders every year**.


Bearing these statistics in mind, MRO operators frequently tell us that the LRT weighs them down – it’s a large tool to be moving around a hangar, and it isn’t fit for purpose with modern health and safety principles in place.


In contrast, the ExLRT is designed to be carried in one hand or attached to the operator with a belt clip.  Can you imagine doing this with an LRT?

weight weight


Size matters


It’s not just the incredible weight difference which makes the ExLRT easier to handle than the LRT.


Take a look at this photo showing the two tools to show the difference in their physical size and footprint.  The overall dimensions make a big difference to how operators can move, handle, and operate the tools.  The ExLRT can be positioned much closer to the section being tested, and it can easily be lifted for placing on a suitable surface.


The dimensions of the LRT are 14 x 14 x 22 inches (355 x 355 x 55mm), giving a total area of 0.07m3.  In contrast, the ExLRT’s area footprint is just 0.009m3 (6 x 8 x 11.8 inches (150 x 200 x 300mm)).


Full of features

Besides the size and weight of the ExLRT, there are so many other features which makes it a next-generation loop resistance tool perfect for MROs. It’s packed full of elements designed to make carrying out mandatory loop tests easier and quicker.


  • To lighten the load even further, we offer wearable solutions for the ExLRT. A harness and belt clip provide flexible, ergonomic options to suit the many positions and angles operators find themselves in.
  • The ExLRT is classified as Intrinsically Safe, so can safely be operated in Class 1 Div 1 (Zone 0) environments. Its outdoor use rating is IP54 so it’s dust and water splash protected.
  • The screen is large and backlit so it can be read no matter how dim or bright the working environment is.
  • Push button controls on the main unit and the probes make the ExLRT very quick to use – operators can accept a reading and move onto the next test in seconds. The probes also have LEDs for immediate pass/fail status.
  • Fed up having to plan for a 2 month calibration turnaround for the LRT? A return-to-base ExLRT calibration is usually just 72 hours.



In short, the ExLRT is a light, modern loop resistance tester designed for MROs. It’s Intrinsically Safe and is approved by The Boeing Company.

How’s that for a weight off your shoulders?

Next steps

Want to see how ExLRT stacks up against LRT in other ways?  Read the full comparison article, or take a deep dive into specific comparisons for how well the tools are designed for MROs, or their Intrinsically Safe credentials.