This chamber set includes all of the components required to form a 250mm diameter mini inspection chamber with a level invert base. The contents are a one piece base and riser section a circular PVC cover and frame.Level invert chambers are often used when the installer has little fall to play with on the pipe run, such as when connecting a new section of drainage to an existing pipe run. A standard mini access chamber has an integral fall from the side inlet to the base, and this can take up valuable height when trying to minimise the fall on the new pipe.The overall depth of the chamber from the invert level to the top of the manhole cover is 612mm. If you need to make small adjustments to the height then the side riser may easily be cut to size using a standard fine-toothed saw.The main channel of the base is left open and the side inlets are blanked off with integral blanking plugs - simply remove the blanking plug by pushing it out from within the base to open and use the side inlets.The cover has a 15Kn load rating making it suitable for use in pedestrian areas.For a brief overview of this chamber please watch the short video below; For a more in-depth description guide to the use of mini access chambers including a visual explanation of the key differences between level invert chambers and normal mini access chambers, please take a look at the more detailed video below.