This Pro Series channel drain kit features an interlocking design which allows each unit to securely lock to the next for a secure, tight fit. The kit comes with the grate pre-installed on the channel. Channel sections connect with interlocking joints; bottom outlet connects to 3 in. & 4 in. Sewer and Drain Fittings; side outlets to 3 in. Sewer and Drain Pipe; end outlet to 3 in. Sewer and Drain Pipe & 4 in. Sewer and Drain Fittings. 72 GPM per ft. flow rate. 23.5 sq. in. per linear ft. open surface area. Rated for NDS Class B Loads (up to 175 psi) when properly installed-recommended for medium-duty pneumatic tire traffic, autos and light trucks at speeds less than 20 mph; ADA compliantPre-assembled channel drain decreases installation time,Modular design makes channel drain flexible for longer runs,Interlocking channel design eliminates the need for couplings,New clip-in feature (channel to channel),Common applications for the NDS Pro Series channel drains include pools, spas, patios, tennis courts and athletic fields.,Extended ribs to make channel more sturdy,New rebar tie clips for easier installation