Oakum
Oakum can be used to seal cast iron pipe drains. After setting the pipes together, workers pack oakum into the joints, then pour molten lead into the joint to create a permanent seal. The oakum swells and seals the joint, the "tar" in the oakum prevents rot, and the lead keeps the joint physically tight.
Today, modern methods, such as rubber seals (for example, gaskets or o-rings) are more common.
Nerf bar
A nerf bar is a tubular device fitted to the side of a racecar, typically single-seat race cars that compete on asphalt or dirt oval tracks. A "nerf" is a small, sometimes intentional, collision between two cars in which one driver bumps the other to facilitate a successful pass. The nerf bar protects the sides of the vehicles and also keeps their tires from becoming entangled. If fast-spinning tires come in contact with each other, one or both of the cars may lose control or even become airborne. These are commonly used on Modifieds such as used in the NASCAR Whelen Modified Series, and the wheel pods behind the rear wheels on a Dallara DW12 INDYCAR is often nicknamed the nerf bar because of the similar purpose.