While the PK01-VS
                  is the lowest factory red dot that I am aware of it is
                  unfortunately almost impossible to find at this time.
                  Fortunately two new red dots are on the market that
                  are almost as low as the VS and are much easier to
                  find, at least as of 2012...PK01-V and PK-A Venezuela.
                
                  PK01-V is almost exactly the same height as VS due to
                  the interesting side rail mount, and fortunately is
                  much more accessible here in the USA than the -VS is.
                  Another interesting aspect of the mount itself is that
                  unlike other AK and universal mounts it has no rear
                  stop to prevent the optic from walking forward. This
                  function is achieved by the clamp itself which has a
                  cam that not only provides tension on the rail when
                  mounted, but extends slightly to prevent the mount
                  from moving forward. When the clamp is in the open
                  position the center cam is flush with the optic rail
                  and will slide off the front, but when in the closed
                  or locked position the other side of the cam extends
                  into the center cutout on the AK rail which keeps it
                  from moving. It's not tricky to get it locked into
                  place in the correct spot but this rail system is
                  different than others I have seen. So far it appears
                  to be working as expected and I have not seen any
                  issues in the few hundred rounds I have fired through
                  my SGL31 with this mount and optic combination. 
                
                  This optic will co-witness with the rear sight leaf
                  set on 1. Battery life is a respectable 500 hours at
                  continuous maximum brightness. As a complete unit
                  including side rail PK01-V weighs 21.7 oz
                  
                
Out of character for most BelOMO optics, PK01-V
                  uses triple-A batteries (AAA) compared to the much
                  more common AA or type 357 watch batteries typically
                  seen. 
                
                
                
                You can see here that the rail is vertical against
                  the receiver but uses a 30mm ring to position it
                  directly over the bore. 
                

              
              
              
              
              
              
              
              
              
 
              


