Guess either I'm too fat for the vest, or I just work it too hard...
Has anyone else's vest's top bolts on the front chest piece fallen off?
I've lost 2 already.
Measuring the remaining bolt, it looks to be a 3mm x 8mm hex bolt.
Can anyone confirm this? Been looking all across the internet and this forum for an answer for the past hour...

Image of Steadicam Merlin Vest with the area I'm mentioning.
steadicam-vest | Flickr - Photo Sharing! (http://www.flickr.com/photos/bernardlau83/8181969856/)

Nope - not a metric bolt. Everything on a Steadicam rig will be SAE (Imperial), since they're made in the US. I believe that bolt could be a 6-32, which would measure out to 3.50mm in diameter, if you've got a pair of calipers handy. Or, if you've got a set of SAE allen wrenches, it should be a 5/64th inch wrench. 8mm would be 3/8" long.

If you call Steadicam (or a local dealer), I'd wager they can put a bag of them in the mail to you, especially if you're still under warranty. Otherwise, you can order them online in many a place, if your local stores don't carry them - I just found a box of 100 of them for a little over $10 at my usual hardware place.

Those bolts really shouldn't be coming loose, and you do risk damage if they do, especially since the top of the vest is plastic. In my 4 or so years of owning and operating with that same vest, I never had them come loose. However, I make it a habit of checking all important bolts (especially those holding the socket block) whenever I do maintenance of the rig. You might also want to get some Loctite or similar non-permenant threadlocker to hold the bolts in, once you've got them replaced.