Quick Summary
The 3F UL GEAR Tyvek Sleeping Bag Cover Liner Bivy Bag Type B is an ultralight bivy-style sleeping bag cover intended for use with a sleeping bag. It is the Type B version, with a stated size of 230 cm x 90 cm, and it folds to 16 cm x 8.5 cm.
The liner is described as DuPont TYVEK / DuPont Tyvek and is presented as a ventilated, moisture-proof layer that helps reduce condensation inside a tent from reaching the sleeping bag. It is not stated as a stand-alone sleeping bag.
Key Details
| Detail | Verified information and buyer relevance |
|---|---|
| Brand | 3F UL GEAR, so the page is for a specific branded item. |
| Product type | Tyvek sleeping bag cover liner / bivy bag, intended to be used with a sleeping bag. |
| Variant | Type B, which is the larger of the two stated versions. |
| Size | 230 cm x 90 cm, which is the key fit and coverage check. |
| Packed size | 16 cm x 8.5 cm, useful for judging storage space in a pack. |
| Weight | 200 g, a useful figure for buyers comparing carried weight. |
| Material | DuPont Tyvek / DuPont TYVEK, the stated material for this version. |
| Use note | Use with a sleeping bag, not alone. |
| Function note | Described as helping with condensation and moisture management rather than rain protection. |
What to Compare Before Buying
- Type and size: Type B is stated as 230 cm x 90 cm. Check that this version suits the sleeping bag and space you plan to use it with.
- Packed size: The folded size is 16 cm x 8.5 cm, so compare that with the storage space in your pack.
- Weight: The stated weight is 200 g. Compare that with the rest of your carried kit if low pack weight matters.
- Intended use: It is meant to be used with a sleeping bag, not as a stand-alone sleep system.
- Weather role: It is described as helping with condensation inside a tent, not as rain or splash protection.
What Is Included
This is the sleeping bag cover liner / bivy bag for Type B. The sleeping bag itself is not included.
Before You Decide
Check that you want the Type B version, with its stated 230 cm x 90 cm size and 200 g weight. Confirm that you are buying a sleeping bag cover liner to use alongside a sleeping bag, and not a complete sleeping bag on its own.
