Specifically Designed To House Raspberry Pi 4B Board, Supports Up To 4 Units ^^ Optimizing Your Workspace, Used For Raspberry Pi Clusters, Video Walls, And More... ^^ 19 X 1.75 (482x44mm), Fully Compatible With 19 Server Racks, Had No Issue Plugging This Into The 1U Rack Space ^^ 4 Slots For Raspberry Pi 4B, Fixed With Included Screw; ^^ The Rack Can Be Vertical Fixed On The Mounting Rail (The Rack Mount Screw Is Included)