Transparent ruler for waveform measurement, capable of measuring frequency and amplitude. I purchased two, and this one was likely unused and stored. Also, because the material is plastic, there may be initial minor scratches. Please refrain from purchasing if you are concerned. - Brand: NIHON KOHDEN - Purpose: Waveform measurement ruler - Color: Transparent/Red - Features: Frequency and amplitude measurement possible - Scale: With Hz and mV markings - Condition: Almost unused Thank you for viewing.