The crimp pins for the JST VH 3.96mm connector have a rectangular shape and are typically made of copper alloy with a tin  plating. These pins are designed to be crimped onto the stripped end of a wire using a crimping tool. The crimp pins can handle up to 4A current and are suitable for use with wire gauge 23/38 SWG, which has a cross-sectional area of 0.42 sq mm of copper.

To ensure a proper and secure electrical connection, it is important to use the correct size and type of crimping tool and pins. The crimping tool used for the JST VH 3.96mm connector is a ratchet-style crimp tool that applies pressure evenly to the crimp pin, compressing it onto the wire. The tool has two separate dies that crimp the insulation and conductor of the wire separately, ensuring a reliable connection.

Using incorrect tools or pins can lead to a poor connection, which can result in electrical problems or even damage to the connector or equipment. When selecting crimp pins for the JST VH 3.96mm connector, it is important to choose pins that are designed for the VH series and are compatible with the wire gauge you will be using. The datasheet or specifications provided by the manufacturer can be a helpful resource for selecting the appropriate pins and tools for your specific application.