Big Agnes Fishhawk 30 Long L. Sleeping Bag Goose Down Insotect Flow. Good condition, no odor or stains, has some feathers poking out at the seams, see photos. Some wear on the velcro. Insotect Flow is a sleeping bag construction technique that combines vertical thermal channels (VTCs) and FlowGate technology to improve the fit, comfort, and efficiency of sleeping bags.