ingeniously simple to use.
The smart pins for securing the turnbuckles are admittedly expensive, but the idea is worth the money. Even without glasses, they're quick and easy to use, so you can do it right away. Previously, the cumbersome fiddling with cotter pins often led to this task being postponed. They're also very quick to release in the fall, meaning you only need to do them right before raising the mast. A brilliant idea.