The Karlak Engine Tachometer Chain Saw Tachometer is a smart addition to your gardening and outdoor needs. Its small design makes it perfect for chain saws with 8 cylinders. It features a digital LCD induction display that displays real-time RPMs from 1 to 99999. This allows you to keep a close eye on your engine's speed, ensuring optimal performance and safety. The built-in CR2450 battery provides a runtime of approximately 45 minutes, allowing you to quickly and easily install it on your chain saw for use in various projects. The Karlak Engine Tachometer Chain Saw Tachometer is not only functional but also stylish, making it a great addition to your collection of automotive and outdoor tools.