X-CELL Optical Tachometer #0524 FOR R/C HELICOPTERS :

The X-Cell Optical Tachometer indicates accurate rotor RPM while flying.
If you can see the rotor, you can measure the RPM, during hovering or 3D aerobatics.
It is great if you don`t have a gov on your helicopter.

Convenient "One-Hand" operation with variable rate rocker switch to increase/decrease rpm in slow mode \(10 rpm per click of rocker switch\) or fast mode \(100 rpm per every second the rocker switch is depressed\).

Features: - RPM range 1000 to 1990 win +/- 1 rpm resolution

Measures any rotating blades, from models to full size helicopters

Largest viewing window for easy tracking of the model in fast flight

Start-up feature automatically begins at 1500 rpm

Automatic battery conservation mode

Automatic "Stand-By" mode after 3 minutes This uses regular 9v Battery...