Nylon 6/6 Machine Screw, Plain Finish, Off-White, Flat Head, Phillips Drive, 12mm Length, M4-0.7 Metric Coarse Threads (Pack of 100): Industrial & Scientific. Nylon 6/6 Machine Screw, Plain Finish, Off-White, Flat Head, Phillips Drive, 12mm Length, M4-0.7 Metric Coarse Threads (Pack of 100): Industrial & Scientific. The off-white nylon 6/6 machine screw has a flat head with a Phillips drive. Nylon 6/6 provides resistance to abrasion, corrosion, and many chemicals and solvents. The material is a strong yet lightweight plastic and is nonconductive. Nylon 6/6 can either absorb or lose moisture, which may alter its dimensions and mechanical properties. The Phillips drive has an x-shaped slot that accepts a Phillips driver and is designed to allow the driver to slip out of the head to help prevent over-tightening and damage to the thread or fastener. The flat head is cone shaped for use in countersunk holes and has a flat top that fits flush with the mated surface.。Machine screws are threaded fasteners that are typically used with nuts or drilled and tapped (threaded) holes. Machine screws are available with a variety of head shapes, which determine how the screw interacts with the mating surface, and drive styles, which determine the type of driver required to install and remove the screw.。 。 。 。