Precision Size: The knitting tensioner accessory measures 21.5 mm wide × 48.5 mm long × 2.5 mm thick with three tension holes sizes (2.5 mm/3 mm/3.5 mm 6pcs per set) which can accommodate all kinds of yarn thicknesses for accurate tension adjustment Transparent and visible design: Made of transparent acrylic this tensioner keeps the row counter visible even with a pull tab attached allowing knitters to easily track their progress and adjust tension boosting both convenience and knitting efficiency Acrylic Material: The tensioner accessories are crafted from reliable acrylic which is sturdy durable tough in texture and has good stability. The material is lightweight smooth and wear-resistant maintaining its shape and durability over long-term use. Not easy to break What It Does: When using an knitting machine this yarn tensioner adapter replaces the need to manually tighten the yarn with your hands. It helps maintain consistent tension while increasing knitting speed making the process smoother and more efficient Easy Installation Features: This acrylic tension regulator features a tool-free installation design eliminating the need for drilling. To use simply thread the yarn through the designated guide opening and adjust to the desired tension level before beginning to knit