You can use this simple piece of code to load the K2 Extra fields in our K2 modules.
Add this code to the template file of the module:
$extraFld = array(); if ($item->extra_fields) { $extraFields = json_decode($item->extra_fields, false); foreach ($extraFields as $key=>$extraField) { $extraFld[ $extraField->id ] = $extraField->value; } }
Now you can call a specific extra field by its id. For example:
echo $extraFld[x];
where x is the id of the extra field.
For an alternative method, check out this article.