public OnPlayerKeyStateChange(playerid, newkeys, oldkeys)
{
    new targetid = INVALID_PLAYER_ID;

    if (newkeys & KEY_LOOK_BEHIND && (targetid = GetPlayerTargetPlayer(playerid)) != INVALID_PLAYER_ID && GetPlayerWeapon(playerid) >= 24)
    {
        new 
            string[8];

        format(string, sizeof(string), "%d", targetid);
        cmd_ar(playerid, string);
    }
    return 1;
}