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Terra Nova says:
The classic bivi designed for minimalist backpacking use, uses Terra Nova Moonlite fabric upper for greater comfort and features a Waterbloc ground sheet for extra durability. A single pre-curved DAC 8.7mm alloy pole provides easy access to the bivi, and the full size mesh door adds maximum ventilation and bug protection.
The Jupiter Lite Bivi is a great alternative to a tent for the solo backpacker. Please note: for maximum safety and comfort, we always recommend the bivi bag zip be left slightly open when in use.