PNG ICO ICNS MORE
Horizon
Battery, low
DimGray
16x16
PNG MORE
Oxygen
low, Audio, volume
22x22
Oxygen-Refit
Audio, low, newschool
128x128
Farm-Fresh Web
low, Contrast
32x32
Silk
voice, low, sound
Fugue
Small, Contrast, low
Human-O2
Audio, volume, low
Desktop apps
Smooth
Farm-fresh
Contrast, low
Computer & hardware
3D
Human o2
volume, low, Audio
UI
Pixel
Fugue Icons
Network & communications
low, sound