The first sight on Cooler Master CM 690 (RC-690) Chassis. Wow… It is big. Cooler Master CM 690 (RC-690) Chassis is mid tower chassis. However, it is bigger than normal mid tower chassis. And heavier too. This is good for overclocker like me. And the version I have come with Transparent Acrylic Side Window Panel. In short, I like Cooler Master CM 690 (RC-690) Chassis.