Key to a new collection of boots by KEEN is KEEN.BELLOWS FLEX technology. The brand says: “KEEN.BELLOWS FLEX requires less energy to bend, making each step feel easier.”
Also: “Built-in flex that makes every step feel easier, bending where other boots crack and weaken over time.”
And: “KEEN.BELLOWS FLEX hikers on average required 60% less energy to bend, contributing to increased efficiency and comfort with each step.”
The flex has been added to a KEEN hybrid hiker-trainer platform with the aim of creating a light and fast boot with waterproof protection and traction on a range of surfaces.
Keen Ridge Flex 
Keen Tempo Flex
Features of KEEN Tempo Flex waterproof hiking trainer boots:
- 4mm multi-directional lugs for traction
- Stability shank for lightweight support
- Speed-lace webbing system with top collar hooks for comfortably snug fit
- KEEN.DRY waterproof, breathable membrane
- KEEN.BELLOWS FLEX in the upper for more bend and less wear
- Recycled PET plastic
- Eco anti-odour for natural odour control
- PFC-free, durable water repellent treatment
- High-abrasion rubber tip for added durability and protection
- Padded tongue and collar for comfort.
- Male and female fit.
- £134.99.
- KEEN
- You can buy from Amazon (I get a small commission for each sale.)
Review: KEEN Tempo Flex waterproof hiking trainer boots
The Flex has been added to Tempo Flex and Ridge Flex footwear (both in mid or low cut). As I understand, the Ridge Flex boot is more of stiff boot for mountain hikes, while the Tempo Flex boot is for hills and trails.
The Tempo Flex WP is an easy boot to like. It offers a generous and comfortable fit. The Flex section does indeed make the footwear feel less stiff. I prefer a boot that easily flexes, so I usually choose one made from fabric rather than leather.
The KEEN Tempo Flex boots are effortless to wear – they are lightweight and comfortable right form the start.
KEEN are never the narrowest of fits but that doesn’t really affect performance and if you have a wide foot you’ll love the shape of the boot.
The footbed is fairly supportive and gives a medium amount of cushioning, which is perfect for hard-packed trails.
There is a good level of padding around the ankle cuff and the tongue. As I had said, the boots are wonderfully comfortable.
The soles are suitable for a range of terrain, such as forest tracks, paths and hill trails.
There is a strip of reinforced rand between the fabric upper and sole on the outer part of the boot but I’d like to see more and all round the boots. This would offer better protection of the boot. I am hard on my boots and I find I wear out the fabric uppers due to rocks and rough vegetation.
I think these boots are better for general lower level walks, such as taking the dog out in local fields, walking on the beach, in woodlands and on country paths.
I would recommend choosing the more robust and durable looking Ridge Flex boots for rougher and more mountainous terrain where you are more likely to face abrasion of the boots, both uppers and soles.
The boots I have been sent to test are light grey and lilac. I am not a huge fan of “girlie” colour schemes but I am sure other women will be. I know I’ll end up with mud and dirt on the boots so they will quickly look grubby. I would prefer a darker colour and laces in a darker colour.
Conclusion: If you are looking for a lightweight and waterproof boot for lower level walks in the country and on tracks, paths and trails, the KEEN Tempo Flex waterproof hiking trainer boots are a comfortable choice. The Flex technology is a bonus and overall the boots are very easy to like. I find myself choosing these boots for a range of walks, form local woodland dogs walks to summer hills and some mountains (where there are trails and less off-the-beaten track hiking.) I would choose a darker colour so they look better for longer. Scotland gets a lot of mud and rain!