Get the Blood Sample using a lancet and lancing device. Test Strips take blood samples automatically on contact when using test strips in a glucose monitor. Results were displayed in 5 seconds. A blood lancet, or simply Comfort Blood lancet, is a small medical device used for sampling capillary blood. A blood lancet is similar to a small scalpel but with a double-edged blade or needle. The lancet is used to make punctures, such as a fingerstick, to obtain small blood samples. Blood lancets are usually disposable. The lancet is also used to puncture the skin in a skin test for allergies