# USB Device Specification — ID 0781:55ab ## Identification - **Vendor ID**: 0x0781 (SanDisk Corp.) - **Product ID**: 0x55ab - **Commercial name**: SanDisk 3.2 Gen1 USB Flash Drive - **Manufacturer string**: USB - **Product string**: SanDisk 3.2Gen1 - **Serial number**: 040123d47e7a47e4ac9e89dd25318ac819d7be0fe18a9961190fdffe1052426fd4ae00000000000000000000a8e587bdff867418ab55810792a96c46 ## USB Characteristics - **USB version**: USB 3.2 Gen 1 (SuperSpeed) - **Negotiated speed**: 5 Gb/s - **bcdUSB**: 3.20 - **Max packet size (EP0)**: 9 bytes - **Power mode**: Bus-powered - **Max power draw**: 896 mA ## Device Class - **Interface class**: 08 — Mass Storage - **Subclass**: 06 — SCSI transparent command set - **Protocol**: 80 — Bulk-Only Transport (BOT) ## Interfaces - **Number of interfaces**: 1 ### Interface 0 — Mass Storage - **Endpoints**: 2 #### Endpoint IN - Address: EP 1 IN (0x81) - Transfer type: Bulk - Max packet size: 1024 bytes - Max burst: 1 #### Endpoint OUT - Address: EP 2 OUT (0x02) - Transfer type: Bulk - Max packet size: 1024 bytes - Max burst: 15 ## Functional Role - USB flash storage device - Removable mass storage - No HID or radio functionality ## Operating System Support - **Linux**: Native support via `usb-storage` / `uas` (fallback BOT) - **Windows**: Native mass storage driver - **macOS**: Native support ## Performance Notes - USB 3.2 Gen1 capable of high throughput - Real-world speed depends on NAND type and controller - BOT protocol limits command queueing vs UASP ## Power & Stability Considerations - High power draw for a USB key (~900 mA) - Prefer direct motherboard USB port - Avoid passive hubs ## Recommended USB Port Placement - Rear motherboard USB 3.x port - Avoid USB 2.0 ports (bandwidth bottleneck) - Avoid shared hubs with RF devices ## Typical Use Cases - OS installation media - Backup storage - Large file transfers - Bootable USB environments ## Classification Summary **Category**: USB Mass Storage Device **Subcategory**: USB 3.x Flash Drive **Criticality**: Low (non real-time device)