Even so they won't shut-off automatically. A voltmeter or hydrometer is necessary to examine the battery situation periodically and switch off the charger, after the batteries are absolutely charged. How Do I Join a Battery Charger-Maintainer to My Motor vehicle? There are 2 methods for connecting a charger-maintainer. The best https://hukums.com/products/stanley-sxwt-ft521-steel-hand-truck-with-120-kg-capacity