... Monocrystalline silicon 3. Polycrystalline silicon 4. High quility Solar panel book / PV panel cell Power: 10W/pc, ttl 20WVmp (Operating voltage): ... alumimum is mainly for improving corrosion resistance .5,Highly transparent , low-iron , tempered glass and antireflective coating6,Excellent ... long tern relibaility 10W Monocrystalline Silicon Solar panel, mini PV panel solar cell 5w 10w 20w 40w