yellow pidg crimptool 59239-4
The 'yellow sized' terminal crimptool is used to crimp terminals in the gauge 12-10 range.
It is also used to crimp non-moistureproof endcaps and non-moistureproof splices.
We use the AMP 59239-4.
Here's a gauge 12 wire that we are going to crimp into a yellow terminal.

The terminal is put in the crimping head of the tool.
terminal inserted

The wire can now be inserted into the terminal.
insert the wire

Like the other PIDG terminal crimps, the wire is inserted and the crimp is made.
Make sure that the rear of the terminal firmly grips the insulation for strain relief. (imagine this terminal to be yellow)
proper terminal crimp
picture by: http://aeroelectric.com/

Now that we have made the crimp onto the terminal we can inspect it.
terminal inspection

The terminal.
the yellow terminal

The crimptool can be set to three different tightness settings. 1 being the tightest.
Looking at the strands of wire we can tell wether the tool should be set tighter or looser.
tightness

The tightness can be set by moving the pegs to holes 1, 2 or 3.
tightness setting

When crimping terminals, splices or endacps with this tool, Here are some more guidelines.
requirements

Some non-moistureproof splices.
non moistureproof splices

Some endcaps, the red non-moistureproof endcap is crimped with the red terminal crimptool, the blue one with the blue terminal crimptool and the hat shaped one with the endsplice tool. The yellow endcap is not shown here but it's the same principle as the blue and the red endcap.
endcaps