The frequency counter has 6 digits and will work from 25MHz up to 200MHz.The best with this counter is that you don't need to connect it with any wires to your equipment. Wires=interference and drift in the oscillation frequency.
This counter use a small pick up coil to probe the oscillation. Just hold the pickup coil a few cm from the main oscillator coil and read the LED.
The LED has 6 digits and the resolution is set to 1kHz.This counter is perfect to check that oscillators are working and at which frequency.