Have you explored the world of cordless garden power tools yet? Cordless power tools have come a long way in recent years, and the current generation of lithium ion batteries are capable of delivering more than enough power and performance to rival the more traditional electric and petrol options.
Our current mower is an electric model, and to cut the whole lawn we need a conga line of extension leads – it’s a faff to set up, a nightmare if the kids are running around, and a pain to navigate while mowing. So I’ve been really keen to explore a cordless product for some time.
This summer I’ve been taking a look at the Stihl RMA339C cordless lawn mower, putting it through it’s paces in our family garden and seeing how it compared to our traditional electric model.
The Stihl RMA339C cordless lawn mower – first impressions
The RMA339C is designed for small to medium sized lawns. It’s very obviously a premium mower. It’s sturdy and the parts look and feel strong and well-made. The housing is a lightweight but tough polymer material that’s resistant to knocks, heat and UV radiation.
This is a cordless mower, powered by a 36V lithium ion battery. If you’ve read any of my other reviews you’ll know that I’m a big fan of cordless garden tools, from both a safety and convenience point of view. But cordless tools still need to perform well, so I was keen to see how the mower compared to our current electric model.
This mower is part of the Stihl COMPACT Cordless System, which means the battery is interchangeable with other cordless products in the range. There are three 36V Lithium-Ion batteries available, each offering a different length of performance. We were supplied with the AK20 battery, which is the mid-range option designed for medium sized gardens. If you have a medium to large lawn, or are concerned about how long the battery will last, I think it’s worth going for the AK20 or AK30 battery.
The AK20 battery takes 150 minutes to fully charge, and is housed on top of the mower. I like the fact that the charge level indicator is clearly visible, making it easy for you to keep an eye on how long you’ve got left before a charge.
The fact that the handle folds flat to the body of the mower ticks a big box for me. We’re tight on storage space in our shed, so this is a big deal and makes the product nice and compact. It takes just seconds to fold the handle down via the press of a lever, and when you’re ready to use it again you just open it out.
There are two carry handles integrated into the top of the mower, which really helps if you need to carry it around. It is quite a heavy piece of kit, and I personally found it easier to wheel it around rather than pick it up.
Performance
For this part of the review, I’m going to talk about my experience with cutting two different lawns. This is because my own lawn is in a bit of a state after so much hot, dry weather. I’ve used the Stihl mower to cut it a few times, but there’s been much less actual grass to mow than usual. Thankfully my lovely neighbours have been taking better care of their lawn, so I was also able to test the mower in their garden on a more ‘typical’ cut.
The RMA339C is quite a bit heavier than our current lawn mower, and I was a little concerned that I’d find it tricky to manoeuvre. Once in action I found it to be surprisingly nimble though. You do need a bit of extra effort to navigate around obstacles or curved lawn edges, but I managed this without a problem. I think this is due in no small part to the wheels; they have a traction pattern and directional stability tread pattern, which makes the mower really easy to control.
I think it’s fair to say the noise level is acceptable. It’s not the quietest mower I’ve ever had, and our electric model is definitely quieter, but it’s not annoyingly loud. It’s a comfortable mower to work with as well, thanks to the height adjustable handlebar. And like the folding mechanism, you don’t need any tools to adjust it. You can access the grass box easily too.
I’ve struggled with tricky blade height adjustment on our mowers in the past, and being honest, it’s been enough to make me avoid changing the height altogether, which isn’t ideal for the lawn. I found the cutting height adjustment on the RMA339C so easy to use; it’s spring-loaded and is a doddle to move, with an easy-to-see scale. You can vary the height between 20-70mm, and you don’t have to flip the machine over or get close to the blades to do it.
I cut our lawn on the lowest blade setting, which was perfect for neatening up sparse, sun-scorched grass.
Here are some shots of the RMA339C in action on my neighbour’s lawn.

Before mowing

After mowing
As you can see, the mower coped well with a lush, dense lawn. It managed the whole area without having to empty the grass box, which is a generous 40 litres. There’s some clever design going on here; the current of air created by mowing ensures optimum filling, while the slits in the box channel the air towards the ground and help prevent dust and dirt being thrown up. There’s a level indicator on the top of the box too. If you prefer mulching your clippings onto the lawn there’s an optional mulching kit attachment available with an RRP of £32.
Stihl have built efficient use of battery into the design too. The mower blades are flow-optimised, which means they cut the grass with minimal resistance and use the battery as efficiently as possible. There’s also an eco mode, which automatically adapts the speed of the motor to the power required – again, consuming minimal battery power and allowing you to get the most out of a single charge.
My verdict
The Stihl RMA339C lived up to my expectations of a premium cordless mower. It’s definitely on the heavy side, which has taken a bit of getting used to, but it’s easy to store and adjust, and comfortable to use. Performance-wise, it did a great job of cutting both dense and short grass, while optimising battery usage. It’s more than capable of dealing with our small lawn, and I think it would easily cope with a bigger area. My favourite feature is the cordless design; it takes all the hassle out of getting setup to mow the lawn, and it’s a really safe option for a family environment. I can’t see us going back to electric any time soon!
I would recommend the Stihl RMA339C cordless lawn mower if you’re looking to make the move to cordless and would like to invest in a high quality product that will give long-term performance. The RMA339C retails at around £350. The AK20 battery has an RRP of £90 and the AL101 charger has an RRP of £30. You can find out more information about the product and your local stockists here.
Could the Stihl RMA339C cordless lawn mower be the perfect option for your garden?
Pin this for later:
Stihl supplied the RMA339C cordless lawn mower, AK20 battery and AL101 charger for review purposes. All opinions and comments are honest and genuine.
Leave a Reply