Yb:fiber free-space polarization-insensitive isolators have been announced by Electro-Optics Technology Inc. for laser marking, stent cutting, micromachining of copper and gold wire, laser welding of dissimilar metals, and elimination of damaging backreflections from workpieces. The PI-09-Yb model features a 9-mm clear aperture and produces a return loss of<-50 dB. It offers 100-W maximum average power handling. Maximum pulsed power handling at 10 ns is 1 GW/cm2. Isolation at 1064 nm and 23 °C is >30 dB, with >94% transmission. Minimum isolation at 1064 nm from 15 to 50 °C is >23 dB. The isolators are compatible with pulsed and continuous-wave Yb:fiber lasers, and their rugged construction makes them suitable for industrial applications.