Method getSizeString

public static function getSizeString($size)
{
    switch ((int) $size) {
        case 3:
        case 7:
        case 1:
        case 5:
            $output = 'm';
            break;
        case 2:
        case 6:
        case 0:
        case 4:
        default:
            $output = 's';
            break;
    }
    return $output;
}