Small, robust, accurate, the cheapest on the market, well-made & will surely last a lifetime, so why only 3 stars????
The legal tyre tread depth for cars is 1.6 mm, straight and pure. Why then do the measurements only give you 1mm graduations (and nothing inbetween)?
I sense that this has been produced mainly for the European & American market (whose laws probably better reflect this guage), but for the purposes of the UK, only an approximation of tread depth can be achieved...
Had they just put one mark at the 1.6 mm point, I would have given it 5 stars... As it is, 0.6 of 1mm is too small a measurement to mark yourself with any great precision, and I wouldn't much fancy the local constabulary having cause to question the accuracy of any DIY job!
I have to say that the guage is usuable, as if the measurement shows below 2mm you're pretty close to illegal if a car & might decide to change your tyre rather than risk 3 points. Having said that, with the hideous cost of tyres & the current recession, you might just want (much like me) to use every last micron of tyre tread available.
Not wonderful... I wonder if the Draper one marks 1.6mm? I would bet it does...
Update: The "32nds" marks in black (I guess these represent 1 inch divided by 32) are seemingly pretty useless EXCEPT that the 2/32nd mark offers the best (closest) approximation of at 1.6mm tread, this mark equalling 1.5875mm (very, very close indeed). So if you CANNOT QUITE see the black line of this marking point, then you have 1.6mm or more. I'm happy with this, but please be cautious if adopting it yourself. I hope that this helps...