digital video recorder h.264 dvr 1.4 channel (2D1+2CIF/4HD1/4CIF), GPS module optional 2.Dual SD cards slots, max 32GB each Digital video recorder h.264 dvr with 2 SD card supported GPS Wifi optional !!Features: 1. 4 channel (2D1+2CIF / 4 HD1 / 4CIF), GPS module optional2. H.264 video compression, Linux operation systems, dual streaming3. Digital timestamp, motion detection4. Dual SD cards slots, ...