Synthetic uppers and lowers. The XS-Pro uppers are well padded and faced with nylon mesh reinforced with a synthetic suede material. The toe is reinforced making it harder to stub toes against sneaky rocks. At the rear of the boot the heel-box is flexible, but seems stiff enough to protect and support and let me get a neoprene socked foot comfortably in there.

These have a bellows arrangement behind the laces rather than a separate tongue. The laces are threaded through nylon fabric loops with two plastic hooks at the ankle. Threading the laces was fiddly but only gets done once or maybe twice. Getting a wader-covered foot into these happens every time and that was a slight chore, loosening the laces until the bellows could open and inserting my delicate plates – it took a judicious application of force. Once in and wriggled to get comfortable, the XS-Pro fits over my ankle and seemed to give some support. Certainly comfortable.

These soles have very proud (and aggressive) hard alloy studs. Do not walk on wooden floors wearing these. And be careful on stone floors, too.

Walking down to the river those long studs meant a lot less slithering than my plain, felt-soled boots. In the water, grip seemed adequate, I think I prefer studs over plain composite soles but still hanker for felt soles on smooth rock.

In my humble opinion, driving a car in these is not a good idea – needless to say wading boots are not designed for that but these studs create a few problems of their own getting a foot from the throttle to the brake pedal.

So, not hot as driving shoes, but as wading boots? Comfortable. Good grip. Very practical.

This type of sole has the added benefit that compared with felt, it is less likely to bring parasites or didymo back with them. And these are more welcome in parts of the word where felt soles have been forbidden.