Edge finder from a pin chuck.

[mklotz]

My interpretation would be a pin vice as having flat jaws and a pin chuck is for holding round items, if you are to copy mine you need removable collets as in your bottom picture.

Pin chuck may be British terminology. Here in the USA, the term pin vise is used for handheld devices that take collets and hold cylindrical items.

As a check, I searched for "pin chuck" on the Micro-Mark (a major supplier of model maker tools) website and got nothing. Searching for "pin vise" produces lots of hits.

A handheld device with flat jaws is usually called a "hand vise" or "jeweler's vise" in USA terminology. Both of those terms return results on the Micro-Mark page.

It's another example of two countries separated by a common language.

Actually, "pin chuck" makes more sense given the use of the word "chuck" with lathes, drill presses, etc. plus the fact that small "pin chucks" are often used to hold small drills in larger chucks that can't close tightly enough to hold the drill directly.

[G.Paul]

Marv
In the part of the us I live in we always called it a pin chuck