18" waterfall opening. Measures 26" x 26" x 26". Provides biological filtration to ponds up to 200 square feet and/or approximately 2500 gallons. Maximum recommended flow 70 gpm. Includes two 2" bulkhead fittings allowing you to enter incoming water from either side of filter. Filter comes standard with three filter pads and two mesh bags for filter media. Ships via UPS at dimensional rates.