Case Lock: Review & Recommendations

Welcome to our big box lock test 2020, where we present you all the box locks we have tested in detail. We have put together detailed background information for you and also added a summary of the customer reviews on the web.

We want to make your purchase decision easier and help you to find the best box lock for you.

You can also find answers to frequently asked questions in our guide. If available, we also offer you interesting test videos. Furthermore, you will also find some important information on this page which you should pay attention to if you want to buy a box lock.

The most important facts in brief

  • Case locks are very easy to install and inexpensive to purchase.
  • The flexible use on many doors is the advantage over conventional mortise locks.
  • Additional box locks and box locks for theft protection also increase security.

Box lock test: The ranking

1st place: case lock universal for PZ with handle set and backplate

This box lock has a high-quality closing latch. It has the dimensions: backset 60 mm, distance 55 mm. As this is a universal case lock, it is suitable for all opening directions.

Everything you need is included in this set. Only the profile cylinder you have to buy additionally.

2nd place: timtina box lock theft protection complete set.

The timtina box lock is a solid lock, which directly provides everything necessary in the set. With this complete set you can secure your trailer at a reasonable price.

It is a galvanized, solid metal housing, which does not rust due to the galvanization. The solid construction and practicality is especially praised by people who have chosen this product.

3rd place: ABUS additional door lock 2110 with rotary knob

The Abus additional door lock convinces with a high-quality external cylinder with profile key according to the manufacturer. The lock can be operated from the inside via a rotary knob and can be securely fastened.

According to the customer, the installation of this product is very quick and easy. Partial customers assembled this box lock in 15 minutes.

The solid workmanship, which can only be destroyed with the utmost force, gives your home more security and you yourself a greater sense of security.

Advisor: Questions you should deal with before you buy a box lock

What is a box lock?

Box locks are a form of screw-on locks. On the visible front side there is only the keyhole and the nut for the handle. The locking mechanism is concealed by a box.

The case lock is also called a surface-mounted or add-on lock. It is usually fitted on the inside of house or apartment doors. The same applies to furniture and chests.

Nowadays, the case lock for apartment doors has largely been replaced by the mortise lock.

However, box locks have the advantage over mortise locks that they require only 2 holes for mounting the box lock. Furthermore, rim locks are mainly used for doors where mortise locks cannot be installed due to their small thickness.

What uses are there for a case lock?

Rim locks are not only available in the form of screw-on locks for apartment or house doors. There are also additional box locks that are attached to the inside of the door to further increase security.
There are also box locks as anti-theft devices for car trailers

However, the main areas of application for box locks are wooden doors, such as a garden gate, cellar door or arbour.

How do I determine the required dimensions?

Since the box lock is only screwed on and not inserted, you need only a few dimensions compared to a mortise lock.
The most important dimensions you need are:

The backset: This is determined by measuring the length from the outer edge of the cuff to the centre of the keyhole.
The distance measure: This measure is standardised in Germany and has either a length of 72 mm, 78 mm or 92 mm. It is measured from the centre of the cylinder recess to the centre of the square.
Square dimension: The dimensions of the square recess can also be important for installing suitable lever handles.
Dimensions of the box: The dimensions of the box do not have the same meaning as for a mortise lock. As the box lock is screwed on, it is not necessary to measure it to the millimetre. The dimensions are nevertheless interesting for the visual impression.

This video shows you the most important measurements and how you measure them:

How do I install a box lock?

You should not worry about installing box locks. The big advantage of this type of lock is that it is so easy to install.
How you mount the lock will be revealed to you when you stand with the lock in front of the door.

Where can I buy a case lock?

You can buy box locks in the following places: Online, at a hardware store or at a security store.
Whether you buy your box lock online, in a DIY store or in a specialist shop depends on your willingness to pay and your interest in advice.
In DIY stores such as Obi, Hagebaumarkt, Hellweg, Toom, Bauhaus and Hornbach you can also get some box locks. A member of staff will help you with any questions you may have. However, the advice will not be as qualified as in a specialist shop.
You will not get any personal advice online. However, as box locks are very easy to fit and not many dimensions are of interest, this is usually not necessary. Most box locks are not used for the front door anyway, but for the garden gate or similar, which makes advice on security unnecessary.

How much does a box lock cost?

Simple rim locks that do not require a cylinder can be purchased from around 10 €.

Box locks that have a profile cylinder are available without profile cylinder from about 20 €. The prices can vary greatly depending on the quality. There are also various sets on offer, where a lever handle and a profile cylinder can also be purchased.

Additional box locks for additional security of the front door can be purchased from about 10 €. Here too, the price increases with the robustness of the lock.

What alternatives are there to a case lock?

The only alternative for apartment doors, which is still the most commonly used today, are mortise locks. Mortise locks have a higher security standard because they are inserted into the door.

Mortise locks are available for the apartment door in many different variants. In addition, electronic mortise locks are becoming more and more popular.

Mortise locks are also available for garden arbours or garden gates. However, box locks are more popular for this use because they are easier to install and security is not the top priority there.

Decision: What types of box locks are there, and which one is right for you?

What distinguishes a box lock for screwing on and what are its advantages and disadvantages?

A box lock or screw-on lock only competes with a mortise lock.

The box lock is characterised by its simple assembly and its universal application possibilities. The box lock requires only 2 cut-outs, which can also be added by yourself, making it ideal for wooden doors.

The only disadvantage compared to mortise locks is the lower security level. Because rim locks are screwed on the outside, they are easier to manipulate.


Easy assembly
High flexibility
Low cost


Lower security level than mortise locks

What distinguishes a box lock for theft protection and what are its advantages and disadvantages?

A box lock for theft protection is used to secure car trailers. If you park your trailer on a public area, you should secure it so that nobody can simply pull it away.

This box lock makes the theft considerably more difficult. Especially as this security device can be bought very cheaply and it makes it easier to park the trailer, there are no arguments against this additional security device.


Low cost
Increased safety
Increased sense of security



What distinguishes an additional case lock and what are its advantages and disadvantages?

An additional box lock is attached to the inside of your house or apartment door. By turning a knob this additional lock is locked from the inside. You can lock the lock from the outside with a key.

Such an additional lock increases security enormously. Burglars must act quickly. Because they have not only one lock to tamper with, but two, they lose a lot of time and are more likely to let the unauthorized entry pass.


Low cost
Increased safety
Increased sense of security



Purchase criteria: You can compare and evaluate box locks based on these factors

There are several criteria by which you can compare and evaluate box locks. The following criteria are important when buying a box lock:

  • Need for security
  • Opening direction
  • Dimensions
  • Trap type

Need for security

The greater the value of what is behind the secured door, the greater your need for security. If you are only securing a few garden tools, you don’t need the highest quality.

However, if you secure your basement door, where some belongings are stored, you should pay attention to high quality workmanship and a high level of security.

Opening direction

Doors can open inwards or outwards and to the right or left.

Make sure that the lock you buy is suitable for the opening direction you need. There are many universal box locks that are suitable for all opening directions.


The dimensions of your door are of course the limiting factor whether the box lock fits or not. If your wooden door does not yet have any cut-outs, then you don’t have to worry about the dimensions not fitting, because you will make them.

Which measurements are important and how you determine them, I have explained to you in the advice section.

Trap type

A distinction can be made between a lifting and a closing trap. Usually many box locks have lifting latches. The advantage of closing latches is that by simply closing the door without locking it, no access can be gained.

Trivia: Worth knowing facts about box locks

Restore antique box locks

There are many people who have a passion for the restoration of antique box locks. On the Internet, some dealers offer restored 18th century box locks for high prices.

However, these prices are also paid because these magnificent, restored box castles are a real eye-catcher.

How do I clean a box lock

There are different methods to clean a box lock. Especially if the box lock is older or even an antique box lock, a cleaning or restoration will make the box lock shine again.

  • Method 1: Soak the lock in caustic soda and then treat it with water. A high-pressure cleaner is particularly recommended. If you don’t have one, you can also try it by hand with gloves!
  • Method 2: Place the lock in a pot, fill it with a solution of ammonia and close the pot. Leave the locks to soak for 24 hours, then brush them off and then dry them in the oven or in the sun.
  • Method 3: This method is the least dangerous. Fill a pot with water and put the lock inside and boil it.

What do I do if the box lock jams or hooks?

If you can no longer operate your box lock smoothly or at all, this can have various causes.

Weather conditions may distort the door, the key may be imitation, there may be dirt particles in the lock or the key may be bent.

The simplest solution that you should try first of all are various sprays and lubricants designed to dissolve dirt and make the lock smoother again.

The following means are recommended:

  • De-icing spray: Mostly used for frozen car locks. However, this spray can also help with dirty door locks.
  • Silicone spray
  • WD40: An agent that is highly effective at dissolving dirt and rust.

Never use household oils because they will stick to your door lock!

How do I pick a box lock?

There are different ways to pick your box lock. These also depend on whether you have installed a cichlid lock or a profile cylinder.

The best known method is the lockpicking method. This is the method in which a lock pick or paper clip is inserted into the lock and the lock is delicately operated.

If you have just excluded yourself or want to know more out of interest, I recommend this video:

What is a locking system?

Locking systems consist of several locking cylinders. These locking cylinders are interrelated.

The characteristic of keyed alike locking systems is that several identical locks can be opened with one key.

With central lock systems, different keys can operate the central lock.

Master key systems are hierarchical systems where there are keys that can open all locks and keys that can only open individual doors. An example of such a master key system is a school.