Did you see this page on their site?
http://www.speedbleeder.com/install.htmThe bleeder has a small one way check valve inside that prevents air from entering during the up stroke of the pedal. The thread sealer, which is already installed on the new bleeder screw, seals the threads preventing air from entering while the screw is unseated. Once the bleeding is completed they seat as normal bleed screws on the conical seat. There is no thread sealer in the first thread or two to allow getting them started into the caliper.
Use a correctly sized socket to install and seat them. The sealer makes them a bit stiffer than a clean thread to install the first time. Once installed they feel similar to a regular bleed screw.
They work well. One of mine lost its sealing as the thread sealer wore out. Not a big deal as the corner can be bled as normal by shutting the screw on the upstroke, or add new coat of sealer.
If taking the car to a shop, let them know they are installed. Loosening and tightening the bleed screw several times can wear off the thread sealer.
Interesting that the bleeder screw head size is Imperial, even with metric threads. I used the metric size on my 2000 Esprit, but did not know ahead of time to use an Imperial wrench.
I had forgot I figured it out.
They work for the clutch slave as well, which is great as access can be more difficult than the brake calipers.
HTH