Bear Grylls Emergency Bivy vs Cypher Climbing Mydas Ultra II
Weight and specs compared for 2026 — and which one to choose.
Tear and puncture-resistant mylar bivy. Only 4 oz for emergency backup shelter.
Full details →Ultralight carabiner at 0.85oz with 22kN rating. Wire gate design.
Full details →HikeLoad is reader-supported. As an Amazon Associate we earn from qualifying purchases, at no extra cost to you. Learn more.
Bear Grylls Emergency Bivy vs Cypher Climbing Mydas Ultra II: which should you buy?
If saving weight is your priority, the Cypher Climbing Mydas Ultra II wins — at 24 g it is 89 g (79%) lighter than the Bear Grylls Emergency Bivy (113 g). That said, the heavier option may justify the extra grams with more capacity, durability or comfort, so weigh the trade-off against how you'll use it.
See where both rank against everything else in this category on the lightest safety page, or browse the full gear weight database.