What is the purpose of this device?

[somenewguy]

http://www.homedepot.com/p/Prime-Line-Gray-Painted-Diecast-Knob-Lock-Out-Device-S-4180/202639100

I guess you're supposed to lock it over the knob (assuming a round or tulip style that fits in the device) so that it spins like a child-resistant cap on a prescription bottle?

It seems very easy to defeat; push on the doorknob though the hole in the device with something like a pencil eraser, or stuff something sticky inside it and then the device will stick to the knob and both will turn together. In fact, I have seen KIK setups where turning the key will turn the knob, which makes this device completely pointless.

Is there something I am missing about how this is supposed to work? If it is supposed to deny access, why would they leave a hole in it?

[cledry]

The hole faces the door and wraps around the lock spindle. So you cannot defeat it as you say. Plus the knob is locked, so this prevents access to the key hole.

[somenewguy]

Ahhh, I get it; the picture shows the back and there is no corresponding hole in the front. That makes sense.

[2octops]

There are a couple of versions of this lockout device. The most popular has no hole in the front for a key to operate and looks like this once installed.



The other actually does have a key hole but the knob is very oversized and will not allow you to insert a key blank completely into the cylinder because the bow of the blank hits the face of the key block before it can go all the way into the cylinder allowing it to turn.

[GWiens2001]

Then there is the third version. You try picking it, and then find that it is attached to a hydraulic ram on a pole that people thought was a knob,

Gordon

[phrygianradar]

Then there is the third version. You try picking it, and then find that it is attached to a hydraulic ram on a pole that people thought was a knob,

Gordon

Only Gordon...too bad 4/1 is just past.