2 Prym revolution counters for knitting.

Prym tachometer most convenient for knitting projects

This accessory, the tachometer from Prym, is a must-have accessory for knitters and is perfect for those who want to avoid counting or recounting the rounds they have done. It is most useful if you are leaving work undone or if you are knitting complex stitches or otherwise with a knitting pattern where needles change.
in this case there are 2 tachometers one ideal for thinner needles and one for thicker needles

Dimensions:
Small tachometer: Ø 2.5 to Ø 4.0mm
Large tachometer: Ø 4.5 to Ø 7.0mm.

Brand: Prym
Material: Plastic
Technique: Needlework