ISO 4165:2001标准适用于道路车辆的电气连接，包括汽车、摩托车、拖车和半挂车等。该标准规定了双极连接的尺寸、形状、材料和电气性能等方面的要求，以确保双极连接的安全可靠性和互换性。

双极连接是指具有两个电极的连接器，通常用于连接车辆的电气系统。该标准规定了双极连接的尺寸为6.3毫米或4.8毫米，形状为扁平或圆形，材料为铜或铜合金。此外，该标准还规定了双极连接的电气性能，包括最大电流、最大电压和接触电阻等。

ISO 4165:2001标准的实施可以提高道路车辆电气连接的安全性和可靠性，减少车辆故障和事故的发生。该标准还可以促进不同品牌和型号的车辆之间的互换性，方便用户进行维修和更换。

相关标准
- ISO 7638-1:2016 Road vehicles — Electrical connections between towing and towed vehicles — Part 1: Connectors for braking systems and running gear of vehicles with 24 V nominal supply voltage
- ISO 1185:2003 Road vehicles — Connectors for the electrical connection of towing and towed vehicles — 7-pole connector type 24 N (normal) for vehicles with 24 V nominal supply voltage
- ISO 3731:2018 Road vehicles — Electrical connections between towing and towed vehicles — 7-pole connector type 12 N (normal) for vehicles with 12 V nominal supply voltage
- ISO 11446:2016 Road vehicles — Connectors for the electrical connection of towing and towed vehicles — 13-pole connector for vehicles with 12 V nominal supply voltage
- ISO 15170:2012 Road vehicles — Connectors for the electrical connection of towing and towed vehicles — 15-pole connector for vehicles with 24 V nominal supply voltage