This is a picture from my instructions when I sell my "flagtastick" effect.
It holds the cane under a jacket, in a box or anywhere you want until the cane is needed. the picture shows it holding a cane open with three silks attached to the end hole.
It is a cotter pin costs about .15 in a ny hardware store.
It has been used by everyone who has my effects including Jeff McBride.
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If you mount this on a table, I drill a hole in the table, and stick either the cotter pin or a 12 penny common nail thru the hole. Then I place the cane on the nail using the slide bar hole (not the silk attachment hole).
Again, I first did this in the late 70's. Some Argentinian dealers have since mentioned this method in the past few years (probably caught my lecture in Miami).

The cool thing is when you pick it up, and slide the cane off the rod, your fingers are all that hold the can from opening.
You immediately get to that position without fumbling to open the furrile.
Note: the photos are from the printed instructions included in my "flagtastick" effect. I also have a video that shows this as well.
This method has been part of the general lecture I do which includes canes and candles. Candle to silk to cane, cane in the air production, I also refer to it as a grenade cane production, when I attach a line to the cotter pin, I pull the line from a distance, and the cane appears remotely.

There are two holes in the ferrule (actually three).
The obvious one is the end hole where the silk goes.
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The next hole is the slide hole. That is where you straighten the ferrule out, stick the cotter pin, bobby pin or rod into it and then allow it (the cotter pin) to hold the cane from opening.
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When production of the cane is required, you grasp as few as two fingers where the silks and hole is (upper hole). Slide the cane off the cotter pin, and now the cane is prevented from opening by your fingers. The transfer of pressure goes from the cotter pin to your fingers.
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It is elegant, as your palm is seen empty, the silks hang as if you are holding a silk or silks (it will not look any different if you did not have a cane.).
There is no movement as normally needed to release the ferrule.
Also, if you have the set-up mounted in the jacket, and you reach for the silks, it looks as though you merely took silks from your jacket as they hang so naturally.
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Oh.. the third hole which can also be used, is the rivet hole.