DeFelsko PosiTector PRBGLS60 PosiTector Gloss Meter - Probe Only - Range: High Gloss, 60° Value: > 70 GU, Measure With: 20°. Compatible with the PosiTector GLS gloss meters, this gloss meter probe is suitable for most gloss applications and is the preferred angle for semi-gloss. In addition, this probe measures at a 60° angle.