4Pcs DC 12V Micro Push Pull Solenoid Electromagnet - Mini Linear Actuator Magnet Valve 4mm Stroke Open Frame - Linear Motion 5.5W 0.15N

These items are very small. They look nice, good quality. It should be fairly easy to connect them to your project. I have not yet energized them.

As expected

Not verry strong. Will need to buy stronger

These are the smallest solenoids I can find, which is perfect for the 40% keyboards I am using them in. They make a very decent amount of noise when whacking a keyboard case. They work as advertised. They do require at least 12v to fire, 9 or 10 absolutely won’t cut it. The reason I am deducting a star is they are dry as a bone out of the package and will not work well without lubrication.

I agree with the many comments about these being too weak. But I decided to review with a 5 star just to explain the point below. The force of 0.15N if you want to feel it before buying is the same as holding 15 grams (~ half ounce) in your hand. Its very light!!!!! I didn't measure the solenoid itself to confirm it delivers 0.15N. But one should expect it to be weak. * Another example: Holding one pound ~454g would generate about 4.5N of force pulling down.