Single-use glass capillary plungers are used to plunge blood from 40ul glass capillaries used by test strips for the CardioChek PA/Plus analyzers. Use the glass capillary to collect a more exact amount of blood for your test with NO blood left in the capillary. Then use the plunger to plunge the collected blood onto the test strip. Using the wrong amount of blood on a test strip can skew the results.