Safety lancets
Fires once and retracts. It cannot be reused by accident, which is exactly what you want in a shared or domestic setting.
What makes it a safety lancet
The needle retracts and locks after it fires, so the lancet cannot be used twice and cannot stick anyone afterwards. That is the whole design, and it is why safety lancets have replaced the older reusable devices nearly everywhere.
They still go in a sharps container. A retracted needle is safer, not absent.
Gauge and depth
A finer lancet hurts less and yields a smaller drop. 28G is the common compromise. If you are not getting enough blood, warming the hand and letting it hang below heart level does more than going to a thicker lancet.
Everything on the box, before you buy.
The incumbents make you register to see a price. The batch and the expiry you are shipped are the ones printed here.
Questions about safety lancets
If yours is not here, the contact form routes to the person who can answer it.