I have created a variable input using the following:

Show as: Buttons

Fixed or Dynamic Views: Dynamic

Dynamic Values: =Concat (distinct Product_Type,'|')

I now have 12 buttons, so far so good!  

What I would like to know is, can I select multiple buttons in one go please? At the moment, I can only select one button at a time, but it would be good to select 3 or 4 in one go. 

Any help on this would be gratefully received.