How Many Chucks Would A Woodchuck Chuck?

That's quite a set!

They are known as pin vices this side of the pond, and possibly have collets instead of chucks sometimes. I only have a few : ( 

For the taps, the horizontal bar becomes useful on metal, partly for the torqueness, but also for the perpendicularity and angle-count (for hand taps). It's easier to keep it straight when there is a long horizontal bar. I use the one in the photo below (for plastic, if it's not going in deep, it's probably less chance of snapping the tap without the long horizontal bar):

(battery shown for size comparison. This tap holder length looks extreme, but this is for small taps (e.g. 2mm or 3mm diameter), and the long length makes it easier to eyeball it straight during turning, plus to count the angle turned.

The blue one on the right is not important, it's just there to show the opposite, i.e. a die holder for making threads.

That's quite a set!

They are known as pin vices this side of the pond, and possibly have collets instead of chucks sometimes. I only have a few : ( 

For the taps, the horizontal bar becomes useful on metal, partly for the torqueness, but also for the perpendicularity and angle-count (for hand taps). It's easier to keep it straight when there is a long horizontal bar. I use the one in the photo below (for plastic, if it's not going in deep, it's probably less chance of snapping the tap without the long horizontal bar):

(battery shown for size comparison. This tap holder length looks extreme, but this is for small taps (e.g. 2mm or 3mm diameter), and the long length makes it easier to eyeball it straight during turning, plus to count the angle turned.

The blue one on the right is not important, it's just there to show the opposite, i.e. a die holder for making threads.