(“Berlin Style” Two Section) 18" wide, acrylic construction, micron bag, Probe holders, Bulkheads, cover & accessory rail Ultra High Flow allows for the high sump flow rates encountered in today's top filtration systems. Our baffle design allows for a bubble free tank return even with the most powerful skimmer attached. Unique constant water level design maintains the same water level in the skimmer compartment regardless of evaporation. This means that the skimmer will always operate exactly as set.