In reply to pad01:
Bleach bottle plastic is the stuff to use. Maplins sell cold temperature zip ties and bits of coathanger wire. Last for ages. If you make them slightly oversize so that there's a wrinkle in them, they pop the snow off too. Make a cardboard template and keep that for reference for the next pair.
Anyway, are you sure you don't mean M10. Mine are still going strong.