View our range of Whale Tufnol® Rod. Whale Tufnol plastic rod is also known as SRBF and is the grade specifically designed for mechanical engineering purposes. This plastic rod is suitable for wear resistant components such as bearings, spacers, bushes and low voltage applications. In addition, dimensionally it is very stable and can be either run dry or lubricated with water, oils or grease. All orders must be placed by 2.00pm for same day dispatched.