HPE 720863-B21 2U SFF Ball Bearing Server Rail Kit

• Brand: HPE
• Option Part Number / SKU: 720863-B21
• Product Type: 2U Small Form Factor Ball Bearing Rail Kit
• Rack Height: 2U
• Rail Type: Ball bearing
• Rail Design: Telescoping
• Server Form Factor: Small Form Factor (SFF)
• Primary Function: Rack mounting and in-rack server service access
• Cable Management Arm: Not included
• Compatible CMA: 720865-B21, sold separately
• HPE Spare/Assembly Reference: 662535-001 is identified by HPE PartSurfer as the rack-mounting rail-kit spare assembly associated with 720863-B21
• Gen8 Association: HPE QuickSpecs identify it as the 2U SFF Ball Bearing Gen8 Rail Kit
• Documented Server Example: HPE ProLiant DL380p Gen8
• Additional Supported Platforms: HPE documentation/PartSurfer records show use with later supported ProLiant configurations; verify exact server model
• Rack Standard: HPE states its rail kits are designed for HPE racks compliant with EIA-310-E
• Compatibility - Ultra Short: Supported 2U SFF HPE servers; verify exact model
• Installation Requirement: HPE recommends a minimum of two people for rack-server installation
• Installation Tool: HPE identifies optional installation tooling for certain rack-server installations; consult the server installation documentation
• Easy-Install Alternative: HPE lists separate SFF Easy Install rail-kit options, including 733660-B21

Why Choose This Product?

• Correct SFF rail selection - Buyers can match the rail kit to supported 2U SFF server configurations instead of selecting an LFF-specific mounting solution.
• In-rack service access - Telescoping rails let technicians pull a compatible server forward, improving access during component maintenance.
• Ball-bearing rail movement - Provides a smoother sliding mechanism for repeated server access compared with fixed mounting arrangements.
• Exact HPE SKU - 720863-B21 gives procurement teams a precise identifier for quotations, replacement planning and infrastructure records.
• Separate CMA procurement - Because the CMA is not included, buyers can order the cable-management component independently according to their rack-management requirements. 
• Useful for lifecycle maintenance - A replacement rail kit can restore rack-serviceability to an existing compatible server without replacing the server itself.
• Rack deployment standardization - Standardizing compatible HPE rail hardware can simplify installation practices and spare-part management across supported server fleets.
• Clear SFF/LFF distinction - The dedicated SFF design helps procurement teams distinguish 720863-B21 from HPE's 2U LFF rail option, reducing the risk of ordering the wrong rail configuration.