Non Hiatt Darbys

Froggatt 

RCS 

Providence Tool 

Jg 

Above and below, Froggatt Darby handcuffs from the authors own collection. These have a dark patina. The cuffs are excellent quality, a tad on the small side. Key not pictured but present. 

Above and below, Rueben, Craddock and Sons Darby handcuffs. This is a nice polished plain steel restraint. Note the two marks near the locking tab; this indicates size two. These are larger than the Froggatt but smaller than many Hiatts, although I do have smaller Hiatts too. 

Note the plain key, and the broad arrow mark at the hinge. 

Above and below, JG 1952 Darby handcuffs with false backstrap. These are small cuffs, and do not fit me, personally. These have a heavy construction and strong springs. 

These have the engraving K.E. 2770 on the inner surface of each lock tube. They are well made, heavy, with a broad shackle. 

Above, a unique cutaway view of the Darby lock tube with showing the interior workings of this simple yet ingenious locking mechanism. 

The spring seen in the upper half of the lock tube is  compressed between the underside of the locking bolt and the fixed plate in the middle of the tube through which the locking bolt passes. This spring tension keeps the locking bolt securely within the locking notch on the end of the shackle. 

When the internally threaded key is screwed into the keyway, the threads pull the locking bolt back against the springs tension once the shoulder of the key contacts the outer edge of the keyway. This retracts the locking bolt and allows the shackle to open. 

The top of the locking bolt which contacts the end cap is angled on the side which faces the shackle, so that the shackles sloped end can depress it and the spring will snap it back shut and locked. Photo from Yossies site. 

Providence Tool Company