This ruler is made from plastic material, which is safe without strange smell. Mainly designed for measuring and knit density of the combined sample. A variety of sizes of needle rings make the size of the needle more convenient and can help you quickly measure the size of the needle without a ruler. Feature -Color:Multi -Material:Plastic -Size:16.00X4.00X0.20cm/6.29X1.57X0.08in - Made of material, it is durable and practical for use. Scales are very clear and accurate, and it is able to be used for a long time. -This product is a great accessory for sewing or knitting, suitable for sewing needle for yarn needles. -With the lightweight and compact size design, it can be easy to take and store. -This sewing ruler is easy to use, making it a must-to-have for your knitting projects. -This needle gauge is for US, UK needle sizes, which can be a good helper for you. Package list: 75 x Rulers