Best Automotive Engine Knurled Head Bolts of 2026

The PrecisionGeek Aluminium Thumb Screws are designed for convenience and efficiency. With a thread size of M4 x 10mm, they provide a secure fit, making them ideal for automotive applications. The knurled head, with a diameter of 10mm and a thickness of 4mm, ensures easy gripping, allowing you to tighten or loosen them without hassle. Additionally, the total length of 14mm adds versatility for various uses. Made from high-quality aluminium in the EU, these screws are both lightweight and durable, giving you peace of mind during installation.

The PrecisionGeek Knurled Screws are custom-made aluminium screws designed for automotive applications. With a total length of 20mm and a head diameter of 10mm, these screws provide a robust solution for your engine needs. Being strong and made in the EU, they ensure durability and reliability. Their knurled head design allows for easy gripping, making installation and removal straightforward for you. This set of four screws offers convenience and efficiency, making them an essential addition to your toolkit.

The Quicksilver Seal 26-8M0058391 is designed for use with the gear case 3/8-16 drain/fill found on most Mercury MerCruiser and Mercury Outboards, except those of Japanese origin. By following your owner's or service manual, you can easily determine its specific applications and installation instructions, ensuring a correct fit. This part is produced by Mercury Marine, meeting high original equipment manufacturer specifications, which helps maximise the performance of your outboard or stern drive. With this seal, you can enjoy enhanced reliability and functionality in your marine engine.