Boveda 8g 58% Humidity Control Packs Hold an Ounce Drier
58% RH is the drier of Boveda's two flower levels, and each 8 g pack holds an ounce there. Moisture moves both directions through a reverse-osmosis membrane, so a jar that has dried out recovers rather than just holding. Food-grade salt, purified water and a thickening agent, and nothing else crosses into your material. Against the 62% version the pack is physically identical, with the same 2.75" x 2.5" footprint, the same fill and the same membrane. Only the equilibrium differs. Seven points sounds small and is not, because it changes how material behaves across months rather than days. 58% suits a long hold and dense material, while 62% suits stock moving to a customer soon.
The 58% RH Choice for Long Term Storage Holds
At 2.75" x 2.5" it seats in the lid holder of small through x-large CVaults, the same footprint as the 62% version. A pack has two clocks. Unopened it keeps two years in the bag, and nothing happens until it comes out. In use it runs two to four months, depending on how often the container is opened. Replace it when the pack turns rigid, which is the only maintenance there is. There is no card and no dot on a Boveda, so the check is done by hand. In a humidor rather than a sealed vault, expect the reading to settle a few points under the labeled figure. The same pack is stocked by the case for anyone running several containers.
Key Features
- 58% Two-Way Control: Adds moisture to a container that has dried out and pulls it back when the lid comes off.
- Protects 1 oz (28 g): Sized so the pack has capacity in hand rather than running at its limit.
- Pure Water Vapor Only: A reverse-osmosis membrane means nothing but water crosses into your material.
- Food-Grade Fill: Salt, purified water and a food-grade thickener, safe resting directly against contents.
- No Activation Required: Active on arrival, so there is no soaking, charging or maintenance step.
- 2.75" x 2.5" Footprint: Seats in a lid pak holder without taking volume that would otherwise hold product.
- Tactile Replacement Signal: The pack turns rigid when spent, so no indicator card is needed.
- Drier Than 62% RH: The right level when material is held long term rather than moving quickly.
Technical Specifications
| Specification | Value |
|---|---|
| Pack Size | 8 g |
| Relative Humidity | 58% |
| Protects | 1 oz (28 g) |
| Pack Dimensions | 2.75" x 2.5" |
| Technology | Patented 2-way humidity control (adds and removes moisture) |
| Composition | Food-grade salt, purified water and a food-grade thickening agent |
| Membrane | Reverse-osmosis membrane — releases pure water vapor only |
| RH Accuracy | ±2% of labeled RH in an airtight container |
| Direct Contact | Safe against stored material; will not damage contents |
| Shelf Life | 2 years unopened |
| In-Use Life | 2–4 months depending on conditions |
| End-of-Life Indicator | Pack turns rigid when spent |
| Activation | None — active on arrival, no soaking or charging |
| Equilibration Time | 24–48 hours to reach target RH in a sealed container |
| Storage When Not In Use | Keep in a sealed bag or airtight container |
| Manufacturer | Boveda Inc. |
| UPC | 852715006330 |
| SKU | MB58-08 |
How Long Does a Boveda 58% 8g Pack Last?
Two to four months depending on conditions, on a roughly three-month replacement rhythm. Frequent opening shortens it.
Boveda 58% or 62% — Which Is Right?
58% runs drier and protects long holds and denser material. 62% keeps more moisture in for jars moving quickly to a customer.
How Much Does an 8g Boveda Cover?
One ounce, or 28 g. The 4 g covers a half ounce and the 67 g steps up to a full pound.
When Should a Boveda Be Replaced?
When it turns rigid. A fresh pack has give like a gel pillow; a spent one feels hard through the wrapper.