Nordfab® supplies multiple, high quality hose types that fit into their ducting systems and are widely applicable.
Rubber Hose from Nordfab® comes in 2 types:
The plumber that installed my new sump pump had the PVC pipe extended to far out from the house. ie: if the grandkids ran pass, they would have inadvertently kicked the pipe, not to mention being in the way of the lawnmower. I had him cut the pipe back up under the rose bush, I then added a 2" X 10' flexible hose, it fit the PVC pipe perfectly, problem solved.