Press the button to switch on WHEELTESTER™. The device notifies of being switched on by beginning to vibrate.		In order to change batteries unscrew the back of the WHEELTESTER™ and open the case. The device uses two N-type 1.5 alkaline batteries. These batteries might not be available in all stores. Certainly you will find these in a photo stores and electronics stores.

The best place to verify working order of WHEELTESTER™ is the car. The device reacts both on lit brake lights when pressing the brakes and on starting the car.		It is advisable to keep WHEELTESTER™ either in a breast or trouser pocket. You can also put the tester into a cigarette case. The working area of the device is up to 2 yards (1.8 meters) from the roulette wheel centre.

WHEELTESTER™ might react on mobile phone during an incoming call if the phone is located too close by. Thus do not keep your mobile phone and WHEELTESTER™ in the same pocket.