The FlashArray//XR2 and //XR3 (representing the FlashArray//X generation) utilize a standardized 3U (3 Rack Units) chassis form factor.

This 3U chassis is the foundation for the majority of the FlashArray//X line, including the //X10, //X20, //X50, //X70, and //X90 models. It is designed to be compact while providing sufficient airflow and space for the dual controllers, two data packs (up to 20 DirectFlash Modules), and power/cooling infrastructure.

Dimensions: Approximately 5.12 inches (13 cm) in height.

Rack Layout: Implementation Engineers must reserve 3U of contiguous space for the base controller chassis. If expansion shelves are included, they typically require an additional 2U each (for SAS or NVMe shelves).

Option B (4U) is not a standard height for current Pure Storage arrays. Option C (5U) refers to the FlashArray//XL , a larger, performance-optimized platform designed for maximum scale and density, which uses a significantly taller chassis to accommodate more expansion slots and power components. Therefore, for the specified R2/R3 X-series, 3U is the correct height.