Miniature 5v push type solenoid - before I contact seller....

EDIT: Managed to answer own question - see second post!

Thinking I would make a tiny musical instrument, I bought a pack of these:

10pcs DIY DC 5V 6V DC Electromagnet Push Small Inhaled Miniature Solenoid

Features :
[For] 5-6V voltage
[Current] about 350mA

I tried several at both 5v and up to 9v, even with the polarity reversed.

I know some solenoids push and some pull. And generally, you connect it to power and it does one or the other. Well, these draw current but does nothing else!

I did find that if you pull the plunger about halfway out, there's a very small point at which it doesn't fall right out or suck itself back in due to magnetism. If you then connect the power, it sucks itself back in, which seems to be rather wrong for a push type solenoid!

I found these all over the internet, but never any instructions. Am I missing a method of "driving" these properly?

I can answer my own question!

I finally got some joy by using Google's "search by image" feature, and here's the same electromagnet, with better description (well, sort of!)

The tail of these Super Miniature Solenoid Electromagnetic Brake is a piece of strong magnetic(NvFeB), when NOT energized, it can suck inner metal core, the force is stonger.When energized (one wire is connected to the positive electrode, another wire is connected to the negative electrode), magnetic is weaken, the inneer metal core can move freely. Thus, its function is equivalent to a mini electromagnetic brake: power-release,and no power-brake.
1 when the wire A is connected to the positive pole,wire B is connected to negative electrode, the magnetic is weaken .
2 In opposite,when B wire is connected to the positive pole, wire A is connected to negative electrode, the magnetic is enhanced.

and

The electromagnet is a bit special ，There is a strong magnet In the end ，if no electricity the magnet will absorbing the shaft , After electrify offset the magnet magnetic , then the Shaft can be activity

In other words, I probably CAN use these, but it's going to require some rubber bands and a bit of annoyance.

I guess the sequence would be:

Find rubber band of right strength.
Ping a positive voltage through the solenoid to get it to release.
Immediately ping a negative voltage through it to suck the core back in, then release the current hoping that the built in sticky magnetism will hold it.

Not really ideal - but hope this helps someone!

Ideally, what I was after was some solenoids of around the same price and size, but that would have a spring and "push" out briefly, to tap against a glass or tuned piece of metal.

Made a video to demonstrate 6V DC Electromagnet Push Miniature Solenoid from ebay. - YouTube