Yes, it is possible. But the right solution for your needs really depends on what you are trying to accomplish.
One issue involves the distance over which you wish to track the keys. For instance, you might have a board on which keys are hung. If you just want to know that one set of keys is present, a short-range high-frequency (HF) system might work well. On the other hand, if you are looking to know where a set of keys is located, in real time and within in a large factory, you might require an active RFID system.
Here is an example of a car dealership tracking keys: Car Dealership Finds RFID the Key to Increased Sales.
—Mark Roberti, Founder and Editor, RFID Journal
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