The Original New 5B21J77093 Lenovo Thinkpad Mainboard is specifically designed for Lenovo laptops, with compatibility for models 21C3 and 21C4. Featuring an Intel I5-1235U processor and Windows operating system, this system board is a reliable and high-quality replacement part for your Lenovo Thinkpad. With alternative numbers 5B21J77093, 5B21J77085, and 5B21J77089, you can trust that this mainboard is a perfect fit for your device. Upgrade your laptop with this genuine Lenovo product for optimal performance and functionality.