Lightweight duck down insulated and comfortable the rab ascent 500 hydrophobic down sleeping bag boasts a toasty 650 fill power wrapped in soft and robust pertex fabric a luxurious feel is derived from the wider shape and spacious foot box whilst the sturdy 5 coil ykk zip with anti snag taping ensures smooth and easy usage the right and left zip versions of the sleeping bag will simply seal together to create a larger sleeping space