... silica with high quality optical finishing and in-house anti-reflection coatings, this Q-Switch exhibits very low insertion ... material: Stainless steel 316Recommended water temperature: +22oC to +32oCThermal switch cut-off: +55oC +/- 5oCOrdering CodesExample: I-QS027-4S4G-N5 ... -ST1 (Q-Switch, 27.12MHz, 4mm active aperture, shear mode, fused silica, ...