The DEC disk images we have archived are organized by type:
RK03 (or more precisely, RK03-KA) disks are single-platter cartridges with a capacity of 2.38Mb. They are used in RK05 disk drives in conjunction with an RK11 Disk Controller.
RL01K and RL02K disks are single-platter cartridges with capacities of 5Mb and 10Mb, respectively, They are used in RL01 and RL02 disk drives with an RL11 Disk Controller.
RX01 diskettes are single-sided, with 77 tracks per side, 26 sectors per track, and a sector size of 128 bytes, for a total capacity of 250Kb (256,256 bytes). They are used in RX01 disk drives in conjunction with an RX11 Disk Controller.