A Framework for Packing a Cave Trip: Backmount Doubles Edition

Tech diving isn’t just about what happens underwater; it’s about meticulous planning for everything that can go wrong—or right. That mindset begins the moment you start planning your trip and extends to packing. Tech diving carries much more gear than recreational diving, but it also means having a tool for every scenario. Your packing list is the first step of the dive plan.

I’m currently certified as an Intro to Cave diver and a Helitrox diver, but for my upcoming trip (September 2025), my goal is to complete my full cave course. This meant prioritizing the essential cave gear and leaving the deco stuff behind (though I’ll happily rent a deco regulator if there’s a chance to dive a sinkhole like Zapote!). Here is a guide to optimizing your own comprehensive packing list.

Pillar I: The Essential Kit

A tech diver’s kit is built on a foundation of redundancy. Everything has a back up, and your packing list should reflect that. This is the foundational gear you need to pack for a successful cave trip. 

• Check with the Pros: Always check with your instructors or guides to see what specific gear they recommend. They can help you with what will trim out better or help you with your weights.
• Backplate & Harness: If you have the space when going to a new place, consider bringing both your Stainless Steel and Aluminum/Carbon fiber plates. One might trim out better than the other, or it could help weight distribution more comfortably while diving.
• Weight System: Most shops who rent tech tanks will have tail weights for rent. However, I now bring a cam band with a weight pocket, just in case a shop doesn’t have them or I need more.
• Regulators: If you use an air-integrated transmitter, you might still want to bring an SPG as a backup. While transmitters are reliable, it’s always good to have a simple mechanical backup.
• Primary reel: Coordinate with your dive buddy. We learned from a previous trip that bringing two reels (a long one and a short one) is great for redundancy and gives you more options to deploy depending on the cave. 
• Backup mask: I use a low-volume free-diving mask with prescription lenses as my backup. It takes up less space in my smaller pockets and ensures I can see if my primary mask is compromised. My buddy, Kevin, uses the same model as his primary mask.
• Gloves: I wear fingerless gloves so my primary light sits better on my hand. I’ve learned my lesson, though, and now wear both gloves to avoid a two-toned tan!
• Hood: I’m always cold so always wear a hood for thermal protection—and to manage my hair!

>> Read more: “skills and equipment required” for overhead courses from Under World Tulum

>> Read more: “Extreme (and Not So Extreme) Multistage Sidemount Cave Diving” with AI by Natalie Gibb  on https://shearwater.com/

For the detail check list, see the infographics and google sheet at the end of the articles with the detail items.

Pillar II: The Travel Plan

This is where the real puzzle begins. Tech diving inevitably requires at least 0.5-1 extra checked bag, but with a bit of planning, you can make it work.

Drysuit Dilemma

The biggest challenge is the drysuit. I’ve tried two ways to pack it:

1. The Carry-On Drysuit: My new drysuit comes with a duffle bag, which makes it easy to carry on. I vacuum-seal my and my buddy’s undergarments and street clothes into a separate 26-inch suitcase. This approach means I have two carry-ons (my backpack and the drysuit bag) and 1 checked bag for my gear and clothing. But then I’ll have to lug the 10lb/5kg drysuit and undergarmet around the airports, not very pleasant if there are flight connections.

2. The Checked-In Drysuit: Kevin and I have also managed to squeeze TWO drysuits and undergarments into a single 29-inch suitcase, with some odds and bits. This is a tighter fit, but it cuts down on the number of bags you have to manage at the airport. Essentially paying for laziness! Best for lots of flight connections.

Carry-On Old and New

The principle of what to carry in carry-on luggage is the same as  Essential Packing blog post – batteries and valuables. In addition to essentials, we added a video light for better sightseeing in the cave. We’re only bringing a simple GoPro on a stick, though. I’m still in learning mode and don’t want to overtask myself with a camera just yet..

Pillar III: Pro-Tips & Hacks

Over the years, I’ve picked up a few tricks that make traveling with all this gear a little easier.

• Protect Your Gear: I still use the same hacks I shared in my“Essential Packing for Single Tank Wetsuit Divers” blog post. I pack my regulators in a vacuum-sealed bag and my lights (without their batteries) in my drysuit boots or fin pockets. I also save all the nice boxes I get from gear brands like Orcatorch to protect my more fragile items.
• One Mask Box: A simple mask box is a multi-purpose lifesaver. I use mine to protect only my two masks. And to protect my glasses and dive computers during the trip.
• The Credit Card Hack: In the US, having a branded airline credit card can likely get you a free checked bag for everyone on your reservation, saving you a significant amount on domestic and even some Caribbean trips. You should always double-check the specific baggage policies on your airline’s website, such as those for United Airlines, American Airlines, and Delta Air Lines.
• First Class Math: I once met a dive shop owner who said he always flies first class with his rebreather because the additional luggage allowance can make the flight price even out, and he gets a bigger seat! It’s worth doing the math.
• The “Rule of Two”: Always remember that most airlines enforce a strict “two-piece” rule for carry-ons (though not necessary weight and size). Be careful—even a fanny pack or a neck pillow can be counted as a separate item!

Ikea BAGs are STILL the VALID HACK!

Cave trips we bring 2 among us: 1 for each person’s gear

Backmount Double Cave Trips Packing Infographics

For a quick visual summary and a handy planning tool, check out my infographics and the Google Sheet link to my detailed checklist below:

• Core Kit: Backplate, harness, wing, and weight system.
• Life Support: Regulators
• Safety & Navigation: Primary light, two backup lights, primary reel, safety reels, jump reels, compass, wetnotes, and two cutting devices.
• Personal Gear: Drysuit, drysuit undergarments, hood, gloves, computer, and backup computer.
• Travel & Logistics: Save-a-dive kit, waterproof bag, and all your drysuit accessories (p-valve, etc.).

Your dive plan starts the moment you book your trips and pull out your suitcase. By being meticulous and having a solid packing strategy, you can ensure your trip begins safely and successfully.

Since now I mostly put my mask in the checked luggage, I always carry it in my mask box. It’s almost waterproof when closed, perfect for storing my glasses while gearing up. After the dive, my dive computer and compass go inside, protecting them from knocks in the crate. I also fill the box with some clothing to save space and provide padding for my mask. It might seem big, but worth it in my opinion!

What’s Next? More Packing Insights!

This post focused on my cave diving (backmount double + drysuit in cave) packing. Stay tuned for future blogs where I’ll dive into specific packing strategies for:

• Liveaboard Trips
• My Travel Wardrobe (Non-Diving Gear)

See here for the packing lists for single tank wetsuit divers: “Essential Packing for Divers: Stay Calm! My Wetsuit, Single-Tank Edition”

Essential Packing Resources

For a quick visual summary and a handy planning tool, check out my infographics and the Google Sheet link below to the detailed checklists:

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Editorial disclaimer

Please be aware that scuba diving is an inherently risky activity, even with certification and experience. The content on this blog reflects my personal opinions and experiences and should not be considered instructional. Always prioritize safety, seek guidance and certification from qualified diving professionals, and carefully consider the risks involved in any dives.