It's so simple to operate that you will not need the instructions - GUARANTEED! If you look at the photo, you can see the four items on the screen. They are ''Y'', for Your dial-in, ''T'' for Their dial-in, 1 for Delay 1 and 2 for Delay 2. This Super Crossover delay box features an ultra bright lighted display and back lit, glove friendly control buttons. It measures a very compact 4-1/2'' x 3'' x 1-3/8'' for easy placement in the cockpit. This box is cross talk compatible. The Little Wizard also features Tap Up/Tap Down for easy setting as well as two delays for a double hit. The Driver Reaction Tester keeps your reaction times down. Compatible with all cylinder engines and ignitions, as well as 12 and 16 volt systems.