Where is this block?

I'm trying to convert @SteveJG's code to my own app, but couldn't find the highlighted block in the image anywhere in the Maths drawer. Can anyone help?
Block4

Taifun

There is no 'Make a list' on the highlighted block. I didn't understand your answer. I did read the discussion.

Dear @Mike_B,
when you say "make a list" do you intend to have a vertical set of operands ? If yes, let me say in a different way what @Taifun has already suggested by directing you to a previous discussion on the matter.

There is the possibility to put the operands of mathematical, boolean, etc operations (blocks) in a vertical ladder by right clicking on the operator (in your case the minus sign), and then select "External inputs" as below:
image

After having selected the "External Inputs" the operator changes like the following:
image

Probably is this what you need ?

@uskiara Yes, that explains it. Thank you.