Practical Tools: Cover a plastic film on your finished diamond canvas, gently scroll the tools on it, will make sure all diamonds are firmly pressed down, no worry the "diamond" fall off, plastic film is beneficial to ensure cleanliness and neatness2-in-1 Design: Design of double bearing, two different size rollers, meet different daily needs; product size: small roller: 6 cm/2.36 inch, large roller: 10.6 cm/4.17 inch, total length: 17.5 cm/6.88 inchNature & Safe Material: rollers made of durable, sturdy hardwood, smooth and wear resistant; connecting shaft is made of thick stainless steel, hard and durableEasy to Clean & Store: Just wash the roller with warm soapy water, and rinse it with clean water, then wipe the left water, keep the roll dry.Various Usage: not only used on flattening diamond painting & canvas, also can be used in sticking wallpaper, pressing craft clay, ceramic & pottery clay, baking, crushing nuts and so on.Please allow 1-2cm errors due to manual measurement