How to make a POS taskpad button or custom POS button for a matrix item?

Hello,

I would like to know if it's possible to create a POS taskpad button or custom POS button for a matrix item (the master item, not the component items under it) so when you hit the button, it would pull up the dimensions screen.  At this moment, it looks like I can pull up that screen only by pressing F2 and double clicking the matrix item. 

Thank you.

A