Ryobi 18v One+ Modular Battery Holder Tower for Ryobi Link Wall Rails This is a vertical battery storage system for Ryobi 18v One+ Batteries that is mounted to Ryobi Link Wall Rails. Being modular, it can be assembled to hold many batteries in a variety of arrangements, but this bundle is for 6 batteries. Each Shaft holds 2 Ryobi 18v One+ Batteries that slide in at a 10-degree angle with a slight gap between them. Shaft pieces connect to each other with included screw & nut. Each shaft has an additional screw hole in the middle to attach it to a bracket (if needed). There is an additional Top, Bottom, and Bracket to complete your assembly. Installation on Ryobi Link Wall Rails begins with the Link Shaft then additional Shafts connect above or below it. The center hole on the Link Shaf