There is provided an endcap, connector, sleeve, and rod system lock designs that can be used to form a customizable shower caddy. The endcap can freely spin without axial movement. The connectors can support product holders at different positions along an extendable rod system. The sleeve can securely connect two rods together. The rod system lock provides a more secure connection between rods of the rod system to easily and reliably lock the rods to their desired combined length.