Engineered with reinforced stainless steel wire handles and natural boar bristles tipped with luxuriously soft wool, these brushes deliver thorough cleaning without scratching delicate surfaces. The thin, flexible wire design (1.9mm and 1.6mm thickness) bends effortlessly to navigate narrow bottle necks, confined tubes, and hard-to-reach spaces. Featuring a convenient end loop for storage and complete dishwasher compatibility, they both practicality and durability for everyday use.