Base or counterbalance for desklamp, magnifying glass, flagpole or something else you need a base for.
I needed a desk lamp for a small corner desk, but most desk lamps were too small, too short or too expensive. Therefore, I purchased a cheap desk lamp with a clamp for the table edge. The clamp is almost worthless and the electricity of course on the side where the lamp can not be mounted. Therefore these two bases so that the lamp (or ...) can be put anywhere you want. The hollow base is intended to be filled with sand for counterbalance so it won't tip over.
There is a low version for smaller lamps or things which needed less, and a higher version for more counterbalance (resp. ca 1.0 and 2.1 Kg). The mountinghole in the middle for both bases is 12.7 mm / 1/2 inch.
The plug for the fill-opening is a separate STL and is the same for both types.
Happy basing :)
PS. If you like the fill-opening and want to use it in your own design, see: https://www.thingiverse.com/thing:3383689
You can use a low infill, the mounting axis for the high version is reinforced and independent from infill and for the low version strong enough as is.