Problem with SELECT

Hello

new to php, and a problem:

$sContentId = $_GET["sContentId"];

$db = mysql_connect("mysql.xxx.nl","xxx","xxx") or die ("Error");

mysql_select_db("keyone", $db);

// here is goes wrong
$sql2 = "SELECT * FROM sContentTbl WHERE sContentId=$sContentId";

	echo $sql2."<br>";
	
	$producten = mysql_query($sql2);
mysql_close($db);

I do only want the (1) item out of the sContenTbl where the value is specified bij $sContentId. But i do get this:

SELECT * FROM sContentTbl WHERE sContentId=\'6\'

If i choose to do it like this (test):

$sql2 = "SELECT * FROM sContentTbl WHERE sContentId=6";

then it works fine.

So what do i do wrong?

Thanks
Mark