 snow clamp
I've had mine on my trailer for 4 years now. They work great. I would
never go back to the traditional tie down after using these. I had a
small accident (no damage) when I hit a deer once. I was hauling my
sled and a deer jumped out of the ditch on the driver's side. I
swerved and missed the deer with the truck but the front of the
trailer caught the deer and took it under. Fortunatly the sled was
loaded on the passenger side and I didn't have a sled on the driver's
side but the trailer with the sled. In driving over the deer though
the trailer had a pretty good jump and the sno clamp held the
snowmobile on very well. I thought for sure after hearing the trailer
and deer collide that the sled would be sitting in the ditch somewhere
but it didn't move.
One thing about them, I would use your own nylon locking nuts when
installing them. The lock nuts they provide only go on, they aren't
made to come off as they damage the threads on the way up. I redecked
my trailer and had to grind off the nuts. I think they're designed
that way for theft prevention but I'd rather be able to remove them if
needed. | 
