Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:5411673.

This is a standoff to increase the distance between NICREW LED lights and the aquarium. It increases height by 7,5 cm. The legs of the light can be press-fit into the slots on the top-side while the lower side slides on the aquarium provided it has a glass-width of about 6,20 mm (in my case a "Blau Aquaristic Cubic Aquascaping 38").