These ties are made of acid resistant polypropylene, so you don't have to worry about them becoming brittle like nylon ties. They are also specially designed for use in battery applications, where they might come in contact with battery acid or fumes (sulfuric acid). This makes them a reliable choice for ensuring safety and longevity. Additionally, these ties are also ideal for use around common water plant chemicals. Their black color is UV stabilized for long-lasting durability, ensuring that they will withstand harsh environmental conditions.