These Ball knobs are constructed using a Technopolymer (Polyamide PA), which gives great heat and cold resistance as well as impact stress resistance. This makes these a strong, robust and durable part. Especially suited for mechanical function components and mechanical engineering, these knobs have many more uses, from cabinet doors to wheel turning these knobs are a great addition or replacement to your old components. This model has a tapped hole but no bushing insert. Features and Benefit: Temperature resistant -40 C to 180 C so can be used in high temperature machinery or in cold environment areas Impact stress resistant to avoid breakages when accidental heavy contact is made Typical Applications: Mechanical engineering Cabinet and storage solutions Automotive solutions