Infusion Sets 21g x 3/4 19mm - Green Winged infusion sets. Designed to be user – and patient – friendly. The ultra-sharp lancet point and the lubricated cannula facilitate needle insertion; the ultra-thin wall maximises flow rates; large colour-coded wings guarantee stability and grip during venipuncture; wings are slightly angled in relation to the cannula in order to conform to the skin surface and to put less pressure on the blood vessel.