From time to time it can happen that the grub screws for the secondary mirror adjustment break

Occasionally, the grub screws for adjusting the secondary mirror can break. Then adjustment is no longer possible.

If we notice this during adjustment before shipping, we will replace the grub screws completely with Phillips-head screws.

We also have replacement grub screws for broken grub screws upon request. However, Phillips-head screws are often found more convenient by astronomers.

You are also welcome to order Phillips-head screws instead of the grub screws.

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