Such a cover for filter holders with a diameter of 26.5mm is for sale. The ring diaphragm offers an inexpensive option for microscopy with oblique illumination up to a magnification of 40x. The cover comes from the 3D printer and you can tell by looking at it - but it works perfectly, is very stable and can no longer be seen in the filter holder anyway.

You are always welcome to take a look at the offer in advance in 08525 Plauen. This is expressly desired in order to avoid any doubts and misunderstandings! The purchase amount must be paid in cash upon collection or in advance via Paypal or bank transfer. Renegotiations are excluded as every interested party had the opportunity to view the offer.