What is an “equal slot ribber”?

The standard ribber dial on an antique CSM has 1/2 as many slots as the cylinder. For example, the 72 slot cylinder used a 36 slot dial. These are called “half slot ribbers”. By contrast, an “equal slot ribber” has the same number of slots as the cylinder it is designed for has needles. In other words, a 72 slot cylinder would have a 72 slot “equal slot ribber.” The equal slot ribber allows for more variations in ribbing, along with the possibility of half pitch ribbing, which would allow you to knit a tube with twice as many stitches as slots in your cylinder, by alternating ribber stitches and cylinder stitches as well as 2×2 ribbing.