SentrySafe Fireproof and Waterproof Lock Box with Key Lock, File Safe with Carrying Handles for Documents, 0.66 Cubic Feet, 14.1 x 16.6 x 13.8 Inches, FHW40100

A compact, purpose-built safe for documents and small valuables

The SentrySafe lock box isn’t subtle about what it’s built to do. The moment I lifted it out of the packaging, the 41-pound heft and chunky walls told me this is a fire and water protection tool first, and everything else—portability, capacity, even day-to-day convenience—comes second. That’s exactly the right set of priorities for safeguarding irreplaceable papers.

Build quality and design

This is a top-opening, clamshell-style file safe with a flat key lock and two included keys. The exterior footprint (roughly 16.6 x 13.8 x 14.1 inches) is substantial for a container in the “lock box” class, and the mass comes from the fire insulation packed into the body and lid. The shell is dense, the hinge feels secure, and the lid closes against a wide, compressible gasket that forms the water seal.

Two inset side handles let you move it around, but be prepared: they’re not for long hauls, and the weight jumps quickly once you add paper, coins, or hard drives. I can carry it solo for short distances, but stairs or longer moves are a two-person lift. If you anticipate frequent transport, plan accordingly.

The flat key lock is best thought of as a privacy/retention lock rather than a serious security barrier. Its primary job is to keep the lid positively latched—especially under heat—so the fire and water seals can do their work. In daily use, the lock has a distinct “press-and-turn” behavior. I’ve had the most consistent results by pressing down on the lid to relieve pressure on the latch while turning the key; you’ll hear a soft click, and then the latch button depresses easily. Closing is the reverse: push the lid firmly until it fully engages, then turn the key. It’s not fussy once you learn the motion, but it isn’t a light-touch mechanism either.

Fire and water protection

The ratings are the main reason to buy this box. It is UL Classified to survive a half hour at 1550°F and ETL Verified for up to 72 hours of water submersion. In practical terms, that means it’s designed to protect paper records and small digital media through a typical residential fire event and the water cleanup that follows.

I did not torch it in my backyard (nor should you), but I did a couple of lower-stakes checks. The safe shrugged off a prolonged shower spray and a partially filled tub test without any moisture getting through to the contents. The lid compresses the gasket evenly, and there’s enough bite in the latch to keep the seal uniform. These are encouraging signs for the scenario this safe is built for: short-duration, high-heat exposure, followed by dousing and possible water pooling.

A practical note: fire insulation in safes like this often contains bound moisture. That’s how they protect paper—by releasing steam under high heat to keep the internal temperature lower. Day to day, that moisture can create a slightly humid microclimate inside. I recommend tossing in a couple of desiccant packs and, for electronics like USB sticks, using a small zip bag or case. It’s cheap insurance against condensation in seasonal temperature swings.

Capacity and organization

Inside, you get 0.66 cubic feet of usable volume, sized specifically for letter-size hanging files. Standard letter hanging folders (not included) drop in cleanly and ride on molded rails. This is the right format for passports, birth certificates, Social Security cards, a stack of letters, deeds, plus a few small valuables like a watch, thumb drives, and an envelope of spare keys.

The tradeoff for the serious insulation is wall thickness. If you’re expecting to stack several three-ring binders or keep oversized albums, you’ll run out of space faster than the exterior footprint suggests. It’s perfect for curated essentials; it’s not the right choice for archiving a decade of taxes in binders, nor will it hold legal-size folders without folding.

A quick capacity benchmark from my use:
- 12–15 letter hanging folders, lightly loaded, fit comfortably.
- Two portable SSDs and a handful of USB drives slip into the front of a folder or a small pouch without crowding the lid.
- A small jewelry pouch or watch case fits in the bottom beside folders, but bulky boxes can make closing awkward.

If you need to access files often, consider using labeled hanging folders so you’re not rifling through stacks. The top-open format makes it easy to see everything at a glance.

Everyday usability

This is a set-and-forget device for most households. I don’t open it daily; I open it when I need a passport renewal, a vehicle title, or to rotate a backup drive. In that rhythm, the weight and latch behavior are non-issues. If you expect to open it every other day, you’ll notice the lid pressure and the key turn, and you might want to store it at knee height to avoid repetitive lifting.

A few practical tips from living with it:
- Placement matters. A closet floor, under a bed, or a low cabinet is ideal. The weight makes high shelves a bad idea.
- Keep the spare key offsite. Glove box or a trusted relative’s home is better than taping it under the safe.
- Use desiccant and revisit it a couple of times a year. Swap packs when they saturate.
- Don’t overload the front of folders. If the lid feels like it’s meeting resistance, redistribute; the gasket needs an even compression.

What it is, and what it isn’t

It is:
- A fire- and water-protective container, with credible, third-party-rated performance.
- A tidy, letter-file-oriented organizer for essential documents and small valuables.
- A durable, single-purpose safe with a straightforward mechanical key lock.

It isn’t:
- A theft deterrent. It’s heavy, but it isn’t bolted down and the lock isn’t designed to resist tools. If burglary resistance is a priority, look for a UL RSC-rated safe you can anchor.
- A high-capacity archive solution. The walls are thick by design; plan for essentials, not everything.
- Ultra-portable. The built-in handles are helpful for short carries, but it’s not a “grab-and-go” box for everyone.

Reliability and maintenance

Over several months, the latch has remained consistent. The press-down-to-unlatch motion feels designed in, not a defect. I’ve had good luck keeping the keyway smooth with an occasional puff of graphite. The gasket has not compressed unevenly or shown any signs of wear. As with any safe of this class, avoid slamming the lid; firm and even pressure is all that’s required.

SentrySafe offers product registration and an after-fire replacement program; I registered mine and recommend you do the same so documentation is on record if you ever need it. Keep your serial number somewhere separate from the safe.

Who it’s for

• Homeowners and renters who want a practical, affordable way to protect essential documents against fire and water.
• Small offices that need a single, accessible spot for corporate records, backups, and a few small valuables.
• Anyone who prefers a key to a keypad—simple, mechanical, and less to go wrong.

Who should look elsewhere:
- Users needing frequent, quick access to lots of paper. Consider a larger, lighter file cabinet plus a smaller fire safe for the truly irreplaceable items.
- Those prioritizing burglary protection. Step up to a heavier, anchorable safe with a recognized burglary rating.

Final thoughts and recommendation

As a document-first safe, this SentrySafe box does exactly what it promises. The UL and ETL ratings give me confidence in its core job; the layout is tailored to letter-size organization; and the overall build feels robust where it matters. The tradeoffs—weight, modest internal capacity relative to the exterior, and a lock that prioritizes retention over anti-theft—are inherent to this category, and they’re reasonable if your goal is to safeguard essentials.

I recommend it for anyone building a sensible home resilience plan: gather the documents you can’t easily replace, add a couple of small backups, and give them a protective home you don’t have to think about. If you can live with the weight and you don’t need legal-size storage or burglary resistance, this is a solid, well-executed choice.