When bolt for internal latching really recommended.

I bought the latch to secure the door from the inside, that is, I just wanted the restrictor function, so you open the door but does not have to completely open.
For this, he is very well suited and makes a solid and reliable impression. I have the latch without the extra locking feature outer mounted (without external cylinder).
That works fine when one considers a few things:

1. the lock case mounted in each case on the first door (as well as specified in the instructions).

2. If the door edge is not at right angles towards the frame, you can see the drilling template (which is flush with the door edge) do not use, because the lock case must survive in order to bridge the slightly sloped bevel in the door edge.
(Actually clear if they had previously been thinking about it ... :-) times.
Thus, if the door edge is not perpendicular (like me), you can set the mounting plate of the lock case directly to the door edge, when placing the lock box to win then about 3-4 mm, bridging the sloping edge of the door.

3. Mount the lock case to an end and then the striking plate mounted by eye on the door frame, the perfect gap between strike plate and lock case is 1-2 mm, then the latch works perfectly.

The outer cylinder (which I have not mounted) is very simple and offers no real protection against burglary such as pulling or drilling. In addition, the assembly is then also a bit more complicated, who has been to cut a 32 mm wood drill or the possibility Nuts reasonable ..?

If you want a reasonable lock and additional protection in the absence I recommend really a reinforced bolt that goes through the entire door width and which one should be mounted by a professional, something like this: 513 848 ABUS PR2600 Tank latch plate, white.

Such a bolt we already have, we needed as I have said something about security when opening the door and, for this bolt is recommended.