Here's how the vaginal birth control ring works, how to use it, and it's benefits and risks. What is a vaginal birth control ring? The birth control ring is a small, bendable silicone ring that ...

However, [Attila Blade]’s version of a free-piston type Stirling engine is simple ... a latex glove, an O ring and some wire. The construction is straightforward as you can see in the video.