Add additional recording capability to your OHP 3000-8, OHP 4000, or OHP 5000...it's simple! Each memory module adds 8 minutes of recording capability to your unit. Just install the memory module in the vacant socket, and the unit automatically recognizes the additional memory. OHP 3000-8 - one open slot. Add one memory module for a total recording time of 16 minutes. OHP 4000 & OHP 5000 - three open slots. Add up to three modules for either 16, 24, or 32 minute recording capacity.