What is "stripper clip"

n. A pressed metal (or plastic) clip, holding a set number of cartridges for a firearm, and used for rapid reloading of the weapon or its magazine.

A stripper clip (also known as a charger or charger clip, especially in British and in Commonwealth military vocabulary) is a speedloader that holds several cartridges (usually consisting between 3 and 10 rounds) together in a single unit for easier and faster loading of a firearm's magazine.