The Hydrosorbent 900 Gram Silica Gel Dehumidifier (the "Large Pack") is the heavy-duty flagship of the Hydrosorbent line. Designed for maximum moisture extraction, this unit is engineered for large enclosed volumes where persistent humidity poses a threat to high-value assets. It provides a massive surface area for absorption, making it the ideal "set-and-forget" solution for serious collectors.
The 900-gram unit is the preferred choice for protecting entire libraries of stamp albums, large safes, or walk-in storage vaults.
Industrial-Scale Protection: This unit provides over 2 lbs of active silica gel, allowing it to handle extreme humidity loads that would saturate smaller canisters in days.
Built-in Indicator System: Features an easy-to-read indicator on the exterior of the box. The window or card transitions from Blue (Dry) to Pink (Saturated), ensuring you know exactly when the unit needs servicing.
Archival & Chemical-Free: The inert silica gel is completely safe for use around delicate paper (stamps/currency), leather, and photographic film. It produces no vapors, odors, or hazardous runoff.
Vented Box Design: The specialized corrugated carton is designed to act as a chimney, pulling moist air through the internal fabric bag to maximize the absorption rate.
Lifetime Reusability: Despite its large size, the unit is fully rechargeable. By baking the internal bag, you can use the same 900 grams of silica gel for decades.
The 900-gram model is the highest-capacity portable unit offered by Hydrosorbent before moving into industrial electronic systems.
| Feature | Specification |
| Model Number | SG-900 (Large Pack) |
| Active Ingredient | 900 Grams (approx. 2 lbs) of Indicating Silica Gel |
| Protection Volume | Covers up to 66 cubic feet of enclosed space |
| Unit Dimensions | 8.5'' H x 6'' W x 2.5'' D |
| Casing Material | Vented heavy-duty corrugated carton (Inner fabric bag) |
| Reactivation Temp | 240°F to 250°F (115°C to 120°C) |
| Indicator Color | Blue (Dry) rightarrow Pink (Saturated) |
Because the 900-gram unit contains a large volume of silica, the reactivation process requires specific care:
Monitor the Indicator: When the indicator turns pink, the unit has reached its 66-cubic-foot capacity limit.
Internal Bag Removal: Open the cardboard carton and remove the inner fabric bag. The cardboard box should never be placed in the oven.
The Bake: Place the fabric bag on a baking sheet in a conventional oven at 240°F
. Due to the volume, this unit requires at least 5 to 8 hours (or overnight) to fully drive off the moisture.
Verification: The unit is ready when the silica beads inside the bag (if visible) or the indicator card return to a deep blue.
Important: Avoid higher temperatures; exceeding 250°F
can damage the fabric of the inner bag. Do not use a microwave.
If you store your H.E. Harris Statesman or Liberty albums in a dedicated walk-in closet or a large floor safe, place the 900-gram unit at the lowest point of the space, as moist air is often denser. For a standard 5' x 5' walk-in closet, two of these units positioned on opposite sides will provide a total of 132 cubic feet of protection, keeping your entire collection in a "museum-dry" state.