Wedges.  They are cut from scrap wood and are a few inches long and  maybe an 
inch square depending on the source.  I always carry a few in the  pocket of 
my beekeeping tool belt.  They can level a hive, stop a hive  rocking on its 
stand, or act as an extra hand when easing open a stuck  hive.  Lever a small 
gap with the hive tool and insert the thin end of the  wedge. You can then bent 
down to see what the problem is or to add smoke without  risking your back by 
supporting the weight and twisting.  This and other  useful tools and tips 
are to be found on the Dorset BKA web site.
 
Chris

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