MTA header?

MTA header?

I'm trying to wire up the Camtronics 5A driver board but met
a "wall". I'm used to screw terminals, molex connectors, etc, but
have never come across the orange and red colored headers supplied
with the 5A kit. I browsed through the Farnell catalogue and saw
something that resembles them described as MTA housing (MTA 156
Housing with lock 5888-854) but don't know how to connect the wires
to them. The catalogue says:

"MTA is a complete PCB interconnection system.... wires can be mass
terminated in one step without wire stripping. ...."

Can someone kindly explain how wires can be connected to these
housing without wire stripping?

Also, the catalogue says "... housing color coded by wire size. 20AWG
(0.3mm2 = orange) but I have what is described as Auto wire size
14/.26 whose external diameter is about 2.5 - 2.7mm (~0.1 in.)

Are auto wire suitable for wiring up motor drivers and connecting
stepper/servo motors?

Thanks in advance

keongsan