Handy, Quick and Easy For DTL, TTL and CMOS High Frequescy Response Instant Indication Pulse Memory Function How to use: 1. Connect RED clip to + terminal and BLACK clip to - terminal of the power source of the circuit under test. The supply voltage should not exceed 18V DC 2. For TTL and DTL, set the upper select switch to the side marked "TIL" For CMOS, set the upper select switch to the side marked "CMOS", contact the probe pin to the point to be tested. The LEDs will indicate its logic states: A. ALL LEDs OFF -High impedance B. RED LED ON - High State (1) C. Green LED ON - low State (0) D. Orange LED ON - Pulse 3. For deteching and storing pulse or level transition, set lower select switch to side marked "PULSE" first. Contact the probe pin to the poin to be tested. The LEDs will indicate is basic state. Then set the lower select switch to side marked "MEM", The orange LED will light when any pulse or level transition is detected. The pulse direction, in comparison with the original basic, state, cabe determined. After use, reset logic probe by setting the lower select switch back to side marked "PULSE" Colour: grey Material: plastic Size: 14 x 3cm Package Contents: 1 x Logic Probe Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours Hope you have a pleasant shopping experience!