Multiple Checkbox Selector In Form Builder

Someone showed me a Dolphin site where the join form has multiple selector using checkboxes.  However, the only thing I see in the form builder is Multiple selector where you hold down the control/options key to do a multiple select.  One has to put a message out because you will be surprised how many interweb users don't know to do this.  Was I looking at an earlier Dolphin that had this multiple checkbox selector or is this a third party add-on?

on my 7.1.4 - i have the option for checkboxes under multiple selector

Thank you, I would have tripped over it and broken my nose LOL.  I never saw it, I was thinking it would be in the dropdown list of the type, multiple selector, multiple selector checkboxes, etc.  I do believe Boonex has the most convoluted way of interface design that I have every seen.  Really, I do.  I am not the only one wasting time finding things in their interface; I see it on here all the time, including just now me and I am not exactly a newbie with Dolphin, being using it for almost a year now.

OK, I just went and looked at this. Why in bleeding heck move it to the advance field?  When I go there I have two bleeding choices, multiple select, and checkboxes.  Why not just include it in the type dropdown list in the first place?  Bleeding heck.