Quick heads up for anyone considering one of these, in a nut-shell, don't bother. Mine actually snapped under quite moderate closing pressure around two miles from the end of a ride around Rivi. The shaft and the bit the lever bears on appears to be made from aluminium of some kind and the thin end of the axle at the lever end breaks way too easily.
If it does break, there's no ready way of repairing it, so you'll be walking the rest of your route.
I did actually do a quick review for the CRC site, saying just this, but surprise, surprise, it hasn't been published.
Complete waste of 25-odd quid and it's going back to CRC just as soon as I have time to stick it in an envelope.
A thoroughly rubbish product.