PNG ICO ICNS MORE
Network & communications
Pixel
16x16 Free Application Icons
secure, Log in, pass
Black
16x16
Key, Log in, login
Lock, security, pwd
PNG MORE
UI
Windows 8 Pack (Metro Style)
private
DarkSlateGray
26x26
Mixed
Random icons
Lock, private, locked
32x32
Computer & hardware
WooCons #1
WhiteSmoke
Mobile apps
iPhone Sidebar icons
Firebrick
Sketchdock Ecommerce Icons
Log in, login, Lock
RoyalBlue
24x24
Log, private, grey
DarkGray
Desktop apps
22 e107-Bubbles
private, e-mail, Pm
SaddleBrown
30x30
DRF
security, safety, secure
Mini
Lock, padlock, private
Khaki