PNG ICO ICNS MORE
UI
Pixel
Gnome icons
Keys, Lock, password
Black
46x48
Tango
Lock, screen, system
32x32
Glyph
Ecqlipse 2
Lock, Unlocked
128x128
Lock
Mixed
3D
Dellipack
vault, Money, Cash
256x256
Computer & hardware
Smooth
Futurosoft
PNG MORE
Twotiny
Folder, Lock
16x16
Evelope, Lock, mail
Network & communications
Oxygen
48x48
Shopping & e-commerce
Siena
green, Lock
Lock, red
yellow, Lock
DRF
security, safety, secure
Desktop apps
KDE Crystal Diamond
22x22
Nuove
Lock, password, secure
Crystal Clear
secure, password, Lock