PNG ICO ICNS MORE
Human-O2
Dialog, exclamation, wrong
Red
128x128
Mixed
Smooth
Angular UI
Halt, Critical, Error
512x512
PNG MORE
Business & finance
Glyph
24x24 Free Application Icons
Error, sign, Blocked
24x24
Files & folders
Spirit20
system, Error
20x20
Computer & hardware
3D
Human o2
Dialog, Error, cross
Desktop apps
Pixel
Splashyfish
Not, Do, Error
16x16
Error
Do, Error, Not
Error, Attention, exclamation