These are SD cards of multiple varieties for your SCSI2SD. (8GB is not recommended, as they cost just as much as 8GB cards, plus 8GB is often not in stock.)
They are high-quality and fast-speed, not Class 4 but Class 10.
They aren't just bare cards, we additionally format and set them up specifically for your sampler. SCSI2SD: SD cards are formatted for your specified sampler/host. ZuluSCSI: We include the proper image files for your specified sampler and set them up for you.