This popular model has been completely re-designed from the ground up to include all of our latest improvements. Lens Ports: The single most important upgrade is our long awaited new Dry Lock (DL) port system. This exciting new system is even more robust and even easier to assembly than our time-tested Four Lock (FL) system. The new ports are lighter and more adaptable, and can accommodate extremely large diameter lenses with ease. If you're considering shooting professional quality lenses like the Canon EF 16-35mm Type II/III or the Canon EF 11-24mm, then the DL system is essential.