Driving ground sleeves into the ground unprotected could result in bending or damage that could make them difficult or impossible to use. For this reason, you should install ground sleeves using these driver caps. These caps will sit perfectly in the tops of these ground sleeves, giving you a surface to strike that will not damage them. As the driver caps will begin to “mushroom” with repeated use, you will need 1 driver cap for every 21 ground sleeves. These driver caps are designed for sleeves with a 2" opening, which are used with 1 5/8" line posts.