PREMIUM MATERIAL- We made this long straw brush set with high-quality 304 stainless steel and high-density nylon bristles. More durable, BPA free and with high elasticity, not easy to deform or rust MULTI-SIZE BRUSHES- The bristles of this 13 pack tube brush sets come with 2, 3, 4, 5, 6, 8, 10, 12, 16, 18, 20, and 25 mm (1/16, 1/9, 1/6, 1/5, 1/4, 1/3, 2/5, 1/2, 2/3, 3/4, 4/5 and 1 inch). The length of each brush is 21 cm / 8.26 Inches, longer than others, suitable for your all needs EASY TO USE- Insert the brush into the pipe, rotate, and remove it for washing. With the long, soft but durable bristle, you can use it to clean each size of tube you have and will not scratch the inside of straws EASY HANGING- Each set of cleaning brushes comes with a detachable keyring that is convenient for fetching, keeping, and hanging WIDELY APPLICABLE- You can apply this bottle straw washing kit for most drinking straw or water bottle straw, teapot necks, and also is suitable for everyday use or family gathering, birthday parties, picnics, weddings, Christmas, travel, and offices, which is easy to carry and can quickly clean the dirt, saving your time and efforts