The Peerless Chain Link Model 700C Handcuffs do however contain a number of slight differences however

As advertised!
Pretty decent weight to them, much the same as the 500's. Nice build quality, a bit dirty (sorry!) and actually has more of a polished finish.

You'll notice that the image above is missing the key-post for one of the cuffs. This is as a result of over-enthusiastic newbies picking them

The first difference we find is in the teeth for the ratchet.

While it looks very similar it actually has a slightly narrower bow track and also a blunter leading-edge(although the teeth look less well formed).
The left is the 700C while the right hand teeth are from the 500's

Much the same as the 500's the 700C's have the standard three locking ratchets in the frame.

Again, there's not much tolerance between the locking ratchets and the frame which means you can shim it down the side...
The other notable difference is in the keyway

Again, The left is the 700C while the right pair is the 500's
The observant among us will note that the keyway on the 700's has a larger radius around the post when compared to the 500's.
In my opinion this makes it easier to pick as a wider variety of tools can be used.
Sadly, they're much the same as the 500's and have no additional security features built in
So in summary:
Shimmable?
- Yes.
Not super easy to shim unless you have some nice thin but rigid metal. If you can get something thin enough down the side that's also good.
Pickable?
- Yes.
Easier than the 500's and you can fit most tools in them
Double locking?
- Yes.
Easily un-done when picking.
A couple of strong knocks against the ground and the double lock has not changed state.
Join?
- Chain linked.
Good quality chain, would be very surprised if it failed
Other vulnerabilities?
- None noted.
Any Type of additional or unique security?
- No.