functions.php concatenate return

Hello,

I have a function which is working well to return a maximum length on my woocommerce products descriptions.

Here is the code:

add_filter('woocommerce_short_description', 'reigel_woocommerce_short_description', 10, 1);
function reigel_woocommerce_short_description($post_excerpt){
    if (!is_product()) {
        $post_excerpt = substr($post_excerpt, 0, 80);
    }
    return $post_excerpt;
}

I would like to concatenate the $post-excerpt var with a string which contains “…” to get something like that as my description:

“blabla blabla…” instead of just “blabla blabla”.

Can you help me please ?

Thanks.