6 x 8, 1-1/2" Durso Standpipe Drain , 3/4" Return Assm.

Three sided Internal Overflow is 6"x 10", has a 1-1/2" Durso Standpipe Drain and a 3/4" Return Assembly with T swivle discharge flare. Used for tanks up to 24" tall.
This overflow is incorporated into the middle of the end or back of your tank ( PLEASE TELL ME WHERE ). It is used in conjunction with a Wet-Dry Trickle filter. The overflow has a Pre-Filter Assembly, which is a layer of filter material wrapped around a standpipe. This is called mechanical filtration, it is what traps particles of debri. Additionally, this internal overflow includes a Return Assembly, this is used to mask the hose that brings the water from the Wet-Dry filter pump below back into the tank. It comes with a barbed fitting below the tank and a swivle discharge nossle that is 2 inches below the water level.
The overflow is black by default unless YOU specify otherwise. All bulkheads are included and all bulkhead holes are pre-drilled. Overflow also comes with a cover and a black-out panel.
See Internal Overflow in out Library Section for more information.