These Crop Bar Kits Are For Use With Our 10ft Wide Polytunnels Giving True Versatility To Your Polytunnel. Made From Galvanised Steel, They Are Fixed Across The Hoops Above Head Height And Can Be Used To Suspend Wires, Canes, Netting Or Hanging Baskets.crop Bars Also Help To Strengthen The Structure, Providing Extra Protection Against Heavy Winds, Particularly On Exposed Locations.kits Are Supplied With Enough Bars To Fit Every Hoop Of Your Polytunnel Excluding The Two End Hoops.