Pre-set qty

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script>
<script>
if (typeof(Ecwid) == 'object') {
Ecwid.OnPageLoaded.add(function(page) {
var pids = [3432333, 3432332, 4543212];
if ('PRODUCT' == page.type)
for(var i=0; i<pids.length; i++) {
if (pids[i]==page.productId)
{
$('input.ecwid-productBrowser-details-qtyTextField').val('5');
}
}
});
}
</script>