This article is from the CD-Recordable FAQ, by Andy McFadden (firstname.lastname@example.org) with numerous contributions by others.
RF4100 (2x2/1MB+;SCSI, based on Philips CDD522 but with different firmware)
CDR4220 (4x2/1MB;SCSI, based on the Philips CDD2000)
CDR4240 (4x2/1MB;SCSI, based on the Panasonic CW-7501)
CDR-4400 (4x2/512K;SCSI, based on the Yamaha CDR-100)
CDR480 (8x4/1MB;SCSI, based on the Panasonic CW-7502)
The RF4102 is an RF4100 with more memory.
The RF4100 does not support disc-at-once recording.