PNG ICO ICNS MORE
Photography & graphic design
3D
32x32 Free Design Icons
locked, Key, secure
Black
32x32
Key, password, login
Gaming & gambling
Photorealistic
48x48 Free Object Icons
locked, Hide, login
48x48
security, privacy, Restriction
private, Protection, security
Antivirus, Guard, Army
Unlock, Safe, secure
security, Lock, secure
Unlock, Key, locked
Network & communications
Pixel
16x16 Free Application Icons
secure, Log in, pass
16x16
Key, Log in, login
Lock, security, pwd
Business & finance
Glyph
Gentle Edges Icon Set
Lock, secure
128x128
secure, Unlocked
PNG ICO ICNS SVG MORE
Mixed
Pittogrammi
Key, secure
512x512
Iconza
secure, locked
Flat UI Icons Free
Unlock, password, secure
Computer & hardware
FS Icons Ubuntu
realplaer, secure, Gnome
UI
Handdrawn
Hand Drawn Web Icon Set
locked, Lock, secure
Desktop apps
Smooth
Windows 7 toolbar full
secure, search, config
256x256
search, secure
search, secure, Clock
search, secure, Unlock
I love icons
secure, locked, Lock