Raspberry Pi Cluster Tray, 1U, 7.5-inch

A 1U tray for our 7.5-inch rack holding two Raspberry Pi Model B-family boards side by side — the official 85 x 56 mm envelope and 58 x 49 mm M2.5 mounting pattern, unchanged since 2014.

Two, not three. A Pi is 56 mm across and the floor here is 156.5 mm; two sit side by side with room for the standoffs and the cabling between them, three do not. A 6U rack of these is eight nodes in four units, which is the density most people were after.

Side by side, not front to back. A second row behind the first would fit the depth easily, and every board in it would have its ports facing the back of the boards in front. Across the width, every board’s connector edge faces its own window in the bezel.

A window per board, not one long slot. The material between the windows is what stops the bezel flexing when two USB cables are pulled at once, and each window is cut to the board’s own I/O rectangle rather than to a generous opening.

In the box: the bezel, the vented floor, and four M4 inserts and screws. The standoff kits are yours — a Pi ships without them and the ones you already have are the right ones.