Polaris Part # 3120150 Round Vent $21.00 ea.You got quite a deal!
There are 8 vents total, the two on the top of the dash (defrost) and the two in the radio area are the same - rectangular. The ones on the passenger & drivers side are square. The two that point at the floor are round. Dryer vent hose is typically 4", the hose you need is about 2" (not positive) but that same material should work. If you find a part number for the round vents let me know, I got a broken one, it was used as a ladder rung to crawl out after a rollover.
The two vents on the top of the dash can be omitted if you want too.thanks for the help guys 114 bucks for the vents from that website going to love the heater this time next year