Edit products

Hi guys a need help finding the .tpl file. On the products page you can select all products and then click on the Choose action button and click the edit selection, a popup box pops up for you to select what fields you want to edit.

That selection box with all the ckeckboxes for you to select the fields, where do i find that .tpl file, i want to add some custom code to it but i can find it any where.

I have looked on the m_update.tpl but that only has the fields when you are actually editing and not the checkbox to select what you want to edit.

Ok i found where i have to put the code that i need but its not sowing up on the pop up selection.

Here is the code that i put on the m_update.tpl file:

{elseif $field == "zero_stock_action"}

Can any one help me in what i’m missing?