You can see a set of the other type Rankin handcuffs mentioned above in this post here (Handcuffs 1800s A.RANKIN PHIL).
This is a very early example of Delestatius/A. Rankin 1861 Model handcuffs with a circular construction (as compared with the later A. Rankin model that had a flat bottom portion with a small half loop to allow finger insertion for opening the cuffs). The handcuffs are stamped "A. Rankin" "Phila" and "Patent" "Dec 10 1861". The handcuffs are complete with original key, solid and fine working. The original EARLY style key is impressive in it's own right. The designs on both sides of the key are hand engraved. This key is different from the keys that I have seen with some online photos of this model of handcuff. Also, I have seen an online photo of this model of handcuffs and the Phila and Patent were in opposite corners than on this pair that I have (not that this makes a difference, but it is different).
A scarce and early set of American handcuffs. - eBay
This set sold for $1,582! (Plus $20 shipping)