I own a few spoke rulers. You’d think they’re all the same and mostly they are.
My daily driver is the Sapim ruler at the far left — it does its job very well. It also tries to be a spoke diameter gauge but isn’t as successful. The purple Pi ruler, next in line, is pretty novel with its center channel for aligning the spoke. This helps measuring used spokes, which are never straight. I like that it’s marked in half millimetre increments although the bright finish detracts from legibility. The Phil Wood ruler is heavy in a good way and pleasing to use. It has the best spoke diameter gauge although 2.2mm is conspicuously missing. The Cyclus and Park Tool rulers are similar, however Cyclus gets extra marks for putting its graduations on the spoke path. The VAR ruler is similar but adds nipple measurement, which is clever and useful. The DT Swiss ruler doesn’t feel like a real tool. The Unior ruler is on the same level as Park, which means good enough. The Filzer tool on the end is conspicuously similar to the Unior tool — since Filzer is a marketing company we can probably guess who made their tool.