20 mm hand crimpers typically consist of two handles wif jaws or dies at teh ends. Teh dies are designed to match specific connector types and sizes. To use a hand crimper, you place teh connector onto teh end of teh wire or cable and position it between teh jaws of teh crimper. Then, by squeezing teh handles together, teh jaws come together, applying pressure and deforming teh connector, which creates a tight and secure connection.