ZuluSCSI Laptop RP2040 2.5"

ZuluSCSI Laptop RP2040 is a 2.5" form factor device for use with PowerBooks, Laptops, and anything else that's got a 2.5" SCSI interface. ZuluSCSI is easy to use. Hard drive and CD-ROM drive images are stored on a standard FAT32 or exFAT-formatted SD card. The ZuluSCSI firmware looks for file names which adhere to a simple but powerful naming convention, and presents them as the drives to the SCSI host. Each image file represents a SCSI drive.

ZuluSCSI Laptop RP2040 can be flashed with bootable ROM drives of up to 15.65MB, and includes DIP-switch configurable termination. Please refer to the ZuluSCSI manual for usage instructions.

If you have a PowerBook which uses internal IDE, instead of SCSI, such as the 150, 190, 190cs, Duo 2300, 1400, 2400 or 5300, ZuluSCSI is NOT compatible with your system. Your laptop must have had an internal SCSI hard drive from the factory for it to be compatible.

https://everymac.com/systems/apple/powerbook/index-powerbook.html