jquery selector for div with class

// all divs with tab_select class
$('div.tab_select')

// first div with tab_select class
$('div.tab_select:first')

// or CSS pseudo selector which is slightly faster than the first jQuery 
// shortcut 
$('div.tab_select:first-of-type')

// or
$('div.tab_select').first()

// or
$('div.tab_select:eq(0)')

// or
$('div.tab_select').eq(0)

if you want a jQuery object use var tmp = $("div.tab_select:first") instead.

var tmp = $("div.tab_select")[0] will return the DOM element (if exists)