This tried and proven armboard design is a great fit wherever you need an armboard.  Easily attaches to an US made operating table side rail.
 
Armboard drops onto rail and locks by means of a weighted trigger lock.
Armboard releases off rail by simply holding trigger lock up and lifting on the outer end of board.
Finger latch trigger on outer end of board allowing for 180 degree rotation
Durable steel casting for longevity
Armboard is made of 3/8″ thick black phenolic and weighs a slim 4.5 pounds
Pad sold separately
Available in 24″ or 26″ long sizes.