This double lot came up today, and the current bid is $338.88 with two bids.  UPDATE: already reached $511.23 with 3 bids while I was writing this post. Knowledgeable collectors know these are extremely rare.  The seller says these are Towers, and is not entirely misinformed, they even throws in some info about Tower but these are much, MUCH more rare.  The top pair is marked Phelps. This is a beautiful example of this rare restraint, and the patina is nice, if not deep.  The bottom pair is in fact an Adams design. The ratchets are on the outside of the ratchet arm. This was a liability to shimming, which Phelps and then Tower improved upon.  I'll link to the Tower page and Phelps post with more detailed history at the bottom of the post but essentially these were based on a prior patent design. Note the square profile of the ratchet arms vs Towers round shackle arm.  In short, the Adams design came first, followed by Phelps getting his own patent on an imp...