Here's what other sites are saying:
The Rab Ultra Bivi is a super lightweight sleeping bag cover made from Pertex Quantum Endurance fabric. Weighing only 8 oz, this sleeping bag cover packs small and is light enough to take on any trip. The Ultra will protect that high quality bag you just bought and keep you dry. If ultra light is what you need, look no further than the Rab Ultra Bivi sleeping bag cover.
The RAB Ultra Bivi is a Lightweight sleeping bag cover made from Pertex Quantum- Endurance fabric.Ultra Bivy Features and Specifications:Lightweight sleeping bag coverPertex Quantum - 30D Endurance fabricMinimal weight and pack sizeShort side zip allows waist height belay and venting optionsLong length allows sitting positionDraw cord hoodCircular toe section allows sleeping bag loftingLightweight welded seamsWorld rsquos first welded stitch free biviWeight:225gColours: BlueSize:2250mm x 930mm
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