The RAM Track Base with RAM ROD Ratchet Attachment provides a strong and durable mounting base for a wide range of uses. Using a T-bolt, the track base attaches to any RAM Tough-Track. With the ratchet attachment, you can connect any RAM component that has a female RAM ROD ratchet connection such as an extension arm or rod holder while the base has a tether point to secure your device. T-Bolt Dimensions: .48" x .95"