Question: I can't remember for the life of me, and google isn't making it easy. e.g. the things labeled 24/40 etc., as in this picture:

[![enter image description here](https://i.stack.imgur.com/9SC81.jpg)](https://i.stack.imgur.com/9SC81.jpg)

Answer: 
They are called Keck clamps.

Here's a link to the page for ChemGlass: <http://www.chemglass.com/product_view.asp?pnr=CG-145>
The clips are named after Hermann Keck - Chemistry World's Classic Kit columnist, Andrea Sella, spoke to him to get the story of the invention before he died a few years ago. <https://www.chemistryworld.com/opinion/classic-kit-keck-clip/3004921.article>