Base Drain Basement Waterproofing Drainage Channel System
This item includes on telescopic inspection port and two 45 degree corner pieces.
Together they make a sweeping curved corner with the inspection port offset from the corner for eas of access after finishing works (eg dry-wall) have been completed.
The curve enhances water-flow capabilities, and ease of cleaning.
The fact that one port is situated in the corner like this means that drain runs along TWO walls can be accessed, thus halving the number of inspection ports necesary on a typical installation.
It is more economical to buy them in this combination rather than separately.