Brilliant design for cupboards (as long as your cupboard door is no greater than 25 mm thick).
Very quick and easy to fit (I did not require any tools to fit the two locks I purchased).
The first one took 10 mins whilst I worked through instructions, which are all pictures and no text.
The second one took about 2 minutes as I was confident from first one that I knew what I was doing.
The instructions do state "For max. adhesion, leave tape to harden for 24 hours. If surface is uneven it is necessary to secure the lock by screwing it into place".
I found the adhesive "tape" on the product worked fine with my flat cupboard doors and I left it for the recommended 24 hours before locking the doors and testing (a toddler and his friends could not budge the lock once it fitted as per instructions).
Note that there are lugs that keep the two parts of the lock in alignment whilst you stick it in place. Once fitted, you simply snap the lugs off so that the two parts of the lock engage freely (in case you were wondering why the lock engagement is not smooth when testing it immediately after fitting it in place). The lugs take a bit of wiggling back and forth to snap off but come away cleanly without the need to resort to tools (although a pair of long nosed pliers may help here if you have difficulty grabbing small items).
If you are frequently using a cupboard and have no need to have it locked for a period of time, you can flick a switch to lock the mechanism in its open position without the need to use the magnetic key to open the cupboard. This feature is a good idea for when you need to use contents of the cupboard frequently when children are out of the way.
The key also comes with a holder that you may stick up high out of reach of children.
You only get one key with each single lock pack but purchasing multiple locks for different doors gives you one or more spares.
I have not ever fixed the product on drawers but can see from the design that it is likely only really useful for top drawers where you can fasten the other half of lock mechanism to underneath of the unit that drawer slides into. If using on lower drawers, then your would somehow need to lock to the underside of the drawer above it, which I can see causing more trouble than it is worth. I could see it being an excellent product for the top drawer of a kitchen unit e.g. a cuttlery drawer for example.
Like I say, I did not use this for drawers, so I have no actually experience fixing to a drawer to test the above theory out.
I hope this helps you make a decision.
In summary, I would not hesitate to purchase again for further cupboard doors I want protecting and also for any top drawers too.
I would probably give this a miss if I wanted to protect lower drawers (i.e. not top drawer) as not sure how it would fit to do this.