Diagnostic Penlights to Examine Eyes, Ears, Throat, Nose, Mouth!. The Black Penlight is for checking eyes and has a Pupil Gauge. The Silver Penlight is for Checking Ears, Throat, Nose & Mouth • 4Pc Set • 2 Black Lights-For Checking Pupil Gauge - Pupil Gauge - Ruler - Warm Light • 2 Silver Lights-For Checking Ears, Throat, Nose & Mouth - White Light • Length : 5.5" • Pocket Clips • Requires 2AAA Batteries (Batteries are Included)