Mammut Smart 2.0 Belay Device Review

25th Aug 2018

Mammut Smart 2.0

There are a lot of belay devices on the market and a growing number of what are generally known as assisted-braking belay devices.  Unlike standard tube-style devices, this style of device helps the belayer hold a falling or hanging climber. They either use moving parts or it is the geometry of the device which applies the braking force.  Either way, these devices make it less tiring to hold a hanging climber, give great control when lowering and can provide an extra margin of belaying safety.

Mammut’s Smart device is a popular assisted-braking belay device which was introduced to the market in 2009 and Mammut recently released an updated design called the Smart 2.0. This new model builds on the significant experience gained with the first model and, says Mammut, ‘offers significantly improved braking effectiveness, optimised geometry and intuitive handling.’   They sent us one to test and we’ve been putting it through its paces over the last few months.....


The Smart 2.0 is designed for use with one rope between the diameters of 8.7 and 10.5 mm.  The device is made from 2 shaped alloy plates that are permanently riveted together with a connecting section which allows the space for the rope to be threaded in just the same way a rope would be threaded into a standard tubular device.  In essence, those are the key features of the Smart 2.0 but that simplicity is also one of the devices key advantages - there are no moving parts to malfunction and the unit is compact and weighs a very lightweight 80 grams.  We were sent a blue colour Smart but there are several colours available and the RRP is £35. 

The Test

We have tried the Smart 2.0 with a range of rope diameter options from skinny’s like the well loved 8.7mm Mammut Serenity (our all time favourite rope) to durable chunky work ropes like our standard 10.5mm Edelrid Towers.  We have used shiny new ropes and furrier older ones and dry treated and standard ropes.  Mostly the ropes used have been dry but there was an occasion where an unexpected downpour meant the rope became unintentionally much wetter!  We haven’t had chance to use the device with iced up rope but, as this is a single rope device, it wouldn’t normally be a device we would use in this context anyway.

The Smart 2.0 has been used for single pitch gritstone and limestone cragging along with sport climbing and it has seen lots of time at indoor walls.  It has also been used by experienced old timers and fairly novice newbies.  

I should also say that, although Mammut offers an addition to the Smart 2.0 (called the Smarter) which is an attachment designed to offer additional security for novices and children.  The Smarter ensures the device will lock even if the rope is held above the Smart.  They also recommend the use of their specially shaped carabiner for optimum performance, but neither of these were available to us during our test period and so this is specifically a test of the standard device which we have deliberately used with various screwgate biners.

In Use

In principle, using the Smart 2.0 couldn’t be simpler - the rope is threaded through the plate (there are diagrams printed on the side of the device to help with that) and a carabiner is clipped into the rope loop and between the side plates.  The rope is then held by the belayer in the brake hand and, by the angle it is held, friction will be applied to the rope when the rope is weighted in any way by a resting, lowering or falling climber.  So, anyone familiar with using a standard tube style belay device will immediately get the basics of using a Smart dialled.

The difference comes when the Smart is loaded.  At this point, the Smart is designed to slide up snug to the carabiner creating a clamping action that locks the rope.  The climber will still need to ensure they are holding the brake rope, but the weight of the climber will be taken until the belayer changes the position of the plate to release it.  It is simple and very effective.

This system works extremely well, but this added function also creates some additional considerations.  Whilst for belaying a seconding climber or a climber on a bottom rope there is nothing additional to be factored in, belaying a lead climber means that some additional care is needed to ensure the rope doesn’t jam up each time rope is paid out - particularly when a quick feed of rope is needed for the leader to clip protection.  Similarly, because the device will have locked up when loaded, the belayer again needs to release the rope in the device to allow rope to feed through for lowering.  

So, the key consideration in how well this device works really revolves around how well the locking system can be managed and whether it hinders the belayer and, in doing so, compromises the safety of the climber.  

Well, I have to say that the first time I took the Smart 2.0 to the climbing wall and belayed a lead climber I did find it a little tricky.  General paying out of the rope wasn’t a problem, but I found it hard to smoothly feed out rope when they wanted to quickly pull some through to clip protection - initially both my partner and I were getting a bit frustrated because they wanted rope quickly and I struggled to provide it.  This isn’t a problem exclusive to the Smart device though and, infact, every assisted-braking device I have used has this tendency because, at the end of the day, they are designed to brake.   

For this type of device it is usually a case of finding the tricks to overcome that 'grabbiness' and the Smart 2.0 is no exception.  I soon realised how important the hand position is and it wasn’t long before I had it nailed. Mammut have designed a curved lip to the end of the device designed to hook your thumb around and this is the solution - when you want to feed rope quickly you simply extend the device to prevent the locking system from kicking in.  It takes a bit of practice but soon becomes second nature.

A similar skill needs to be developed when lowering a climber.  As the device will lock, it needs to be unlocked to lower and the same curved thumb hook can be used to angle the device to allow rope movement.  I again found my lowering was a little jerky to begin with but this is soon solved and then the device is smooth and efficient.

I used the device with 8 different HMS style screwgate carabiners and really, in all honesty, I found it worked well with them all.  A broad radius carabiner like the DMM Aero offered the smoothest action but even smaller radius ones worked fine.  The specially designed Mammut Smart carabiner definitely looks like it will offer a smooth action and has the additional benefit of a plastic plate to ensure the gate can’t be accidentally opened and also can’t be cross loaded. This might make a worthwhile investment and Mammut also sell the belay device and carabiner as a set.      


So, to summarise the Smart 2.0 - I really like it!  I like the fact that it is simple, that it has no moving parts, that it is light and that it is intuitive to operate (particularly for anyone used to a tube style device).  I also like the fact that is offers a definite improved level of security and, particularly for belayers holding climbers that are working routes or hanging on the rope a lot, it is very comfortable and less fatiguing to use.  I like that it is durable and that it works well for beginners. I also really like that it comes in a lot cheaper than many other assisted-braking belay devices on the market.   

I like it all, but users should also be aware that to achieve the skills for efficient and smooth braking, paying out and lowering will take a bit of practice and this should be tried in low risk situations until the belayer is confident and proficient.  It is another great Mammut product and comes highly recommended.  Full details can be found on the Mammut website here and the handy video below tells you all you need to know......

Posted by Paul