The boxes have been engineered with security at the forefront. The boxes are constructed of 1/4” solid steel with the back plate welded onto the shell housing with a continuous weld. We use only high security lock cores that are UL tested and meet the requirements of UL 437. Knox has taken the extra step of providing additional strengthening of the lock cores from UL 437 to provide an even higher level of security.As stated, the proper installation of the box is paramount in the security of the box. Per the Knox installation instructions, all boxes should be attached to a solid wall, beam or post using at least 4 Grade 5 or 8 fasteners of 3/8” diameter. If the box is mounted on a secure wall per the Knox installation instructions, it will be extremely difficult to knock the box off the wall.
Knox recommends using 3/8” Grade 5 or Grade 8 fasteners and large, thick steel washers to mount the KNOX-BOX to a solid concrete wall. Mounting to a hollow surface requires use of a steel backplate as well, but in either case, the most critical mounting component is the fastener that attaches the KNOX-BOX to the wall. If it is not Grade 5 or Grade 8, the fastener is not strong enough.
Grade 5 Fasteners can be identified by three marks on the bolt head and Grade 8 Fasteners have six marks:
Knox recommends use of Grade 5 or Grade 8 Fasteners for all KNOX-BOX installations
As an added layer of security, we offer an optional alarm tamper switch on all our boxes. When the tamper switch is connected to the building’s alarm system, an alarm is sounded if the box is opened with a key or removed from the wall.
While we cannot guarantee that a determined thief or vandal will never be able to get a KNOX-BOX off a wall, we have spent over 35 years making our product as tamper resistant as possible. Most thieves/vandals would find it far easier to break into a commercial building than a KNOX-BOX.
Underwriters Laboratories performs several types of attack tests on our product before granting the 1037 attack-resistant rating, a hammer test being just one of them. Knox engineers perform various internal “attack-tests” on our product as well. Here is a video we can share showing the effects of various sized hammer-blows on a properly installed 3200 Series surface-mount KNOX-BOX. A recess-mount KNOX-BOX would be even less susceptible to this type of hammer attack as it is mounted flush with the building wall.
Notice that other than cosmetic damage, the Knox-Box can literally take a beating. In fact, the KNOX-BOX will eventually warp under repeated sledge blows and actually become more secure by wedging the door inside the shell.