Glossary
Insulin syringe
Also written U-100 syringe, U-40 syringe, slin pin
A small syringe graduated in units rather than millilitres, most commonly with a U-100 scale.
Insulin syringes come in 1 mL, 0.5 mL and 0.3 mL barrels. A smaller barrel spreads the same range of doses over a longer scale, so small volumes are easier to measure accurately.
The graduation spacing also varies: a 1 mL U-100 barrel is typically marked every 2 units, while 0.5 mL and 0.3 mL barrels are usually marked every unit. A dose that lands between printed marks cannot be drawn precisely.
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