Product review (5 stars): Great Hoses for Flushing Tankless Hot Water Heater
I purchased these hoses to flush my tankless hot water heater.  After reviewing kits online that cost more than $100, I bought a little Flotec drill pump and this pair of rubber washer hoses.  The hoses hooked up flawlessly and solved my problem at a great price.  One hose fed the pump, the other hose flowed from the pump into the cold water inlet, the hot water outlet flowed back into the bucket with no hose.  I was pumping white vinegar through the hoses.  This caused some discoloration of the metal hose end soaking in the vinegar bucket, but nonetheless worked just fine.