40L Duffel Bag – Waterproof Zip Duffel in Welded TPU with Window Pocket, SL-C437
Product Description
Product Detail
At a Glance
| Model | SL-C437 |
| Capacity | 40 L |
| Dimensions | 52 × 28 × 28 cm |
| Weight | 1.1 kg |
| Material | TPU-laminated 420D nylon |
| Construction | High-frequency welded seams |
| Closure | Waterproof top zip with buckle-strap end lock |
| Water rating | IPX6, heavy rain and spray; not submersible |
| External storage | Welded zip pocket with clear grid window |
| Carry | Long twin handles, hand or shoulder carry |
| Colour | Charcoal with red trim; custom colours available |
| MOQ | 300 pcs |
| Lead time | 30–35 days after sample approval |
Product Description
SL-C437 is a 40L duffel bag, holding 40 liters in a box-shaped body measuring 52 × 28 × 28 cm and weighing 1.1 kg. The body is charcoal TPU-laminated 420D nylon with all seams high-frequency welded. The main compartment opens through a waterproof zip that runs along the top and down one end, marked by two red trim lines. At the end of the zip, a webbing strap with a side-release buckle closes over the zip tail and holds it shut. On the front panel sits a welded zip pocket whose face is a clear PVC window reinforced with a grid, so the contents can be seen without opening it; the pocket zip has a red rubber pull loop. Two long webbing handles are anchored on welded patches that run down both faces of the bag, long enough to carry by hand or over the shoulder. Each end cap carries a webbing buckle strap and a D-ring with a red rubber loop for clipping gear or a shoulder strap.
Closure and Water Behaviour
The main zip is a waterproof zip, which opens the full length of the bag for packing and unpacking like a conventional travel duffel, without the folding of a roll-top. The buckle strap at the end of the zip closes over the zip tail, the point where most zips let water in first, and stops the slider from working loose in transit.
The rating is IPX6, verified by heavy rain and water-jet testing on finished bags. With the zip closed and the end strap buckled, the main compartment stays dry in heavy rain, on a boat deck in spray, or on a wet dock. The bag is not built to be submerged, and the zip is waterproof rather than airtight. The front window pocket uses a water-resistant zip and is meant for items that can tolerate a little moisture.
Construction
The body seams, the window pocket frame and the handle patches are high-frequency welded, so no stitching runs through the waterproof wall. The handle webbing is sewn only to the welded patches, and the patches extend down the faces of the bag so the load of a full duffel spreads across a wide area of fabric instead of pulling on a single point. The box shape, with flat end caps and a flat base, lets the bag stand upright and stack in a car boot or a boat locker.
Engineering Specifications
| Model | SL-C437 |
| Capacity | 40 L |
| Dimensions | 52 × 28 × 28 cm |
| Weight | 1.1 kg |
| Recommended load | Up to 15 kg |
| Water rating | IPX6, heavy rain and water-jet test; not submersible |
| Seam construction | High-frequency welded |
| Attachment points | Welded patches, no stitching through the waterproof wall |
Material Specifications
| Body | TPU-laminated 420D nylon, charcoal |
| Main zip | Waterproof zip with red trim |
| Pocket zip | Water-resistant zip, red rubber pull loop |
| Window | Clear PVC with reinforcing grid |
| Webbing | 25 mm and 38 mm polyester |
| Buckles | Side-release, acetal |
| Loops | Red rubber pull and clip loops |
Functional Specifications
| Main compartment | Single open compartment, full-length top zip |
| Zip lock | Buckle strap over zip tail |
| External storage | Front zip pocket with clear grid window |
| Carry | Long twin handles, hand or shoulder |
| Attachment | End buckle straps and D-rings with rubber loops |
| Stability | Flat base and end caps; stands upright |
Customization and OEM
| MOQ | 300 pcs per colour |
| Capacity | 40 L standard; 30 / 60 / 90 L on request, or as a matching set |
| Colour | Pantone matching on body, trim and webbing |
| Logo | Screen print, heat transfer, welded patch, print behind the window |
| Fabric | TPU on 420D / 840D nylon, PVC tarpaulin, GRS recycled base |
| Closure | Waterproof zip standard; airtight zip on request |
| Accessories | Detachable shoulder strap, backpack straps, internal pocket |
| Sample | 7–15 days |
Packaging Specifications
| Unit pack | PE polybag with suffocation warning |
| Carton quantity | 12 pcs per export carton |
| Labelling | Barcode, SKU, country of origin as specified |
| Options | Hangtag, colour box, retail header |
Recommended Use
Weekend and short-haul travel, boating and sailing trips, fishing and camping trips, gym and sports kit, and car travel where a bag that stands upright and stacks is useful. Suitable for clothing, towels and soft gear. Not intended for submersion; keep electronics in a separate dry pouch.
Quality Inspection Standards
Every production run is checked at IQC, IPQC and OQC. The suite covers load testing to 1,500 cycles, zipper fatigue to 3,000 cycles, tensile and bonding strength on welded seams, handle patches and the window frame, buckle pull and release testing, abrasion on the base, colour fastness and colour difference against the approved sample, and heavy rain and water-jet testing on finished bags. Third-party inspection by SGS or QIMA can be arranged at the buyer's cost.
Product Highlights
40 L zip-top duffel that opens the full length for easy packing. Buckle strap that locks the zip tail. Front welded zip pocket with a clear grid window. High-frequency welded TPU body with welded handle patches, so no stitching runs through the waterproof wall. Long twin handles for hand or shoulder carry. Box shape that stands upright and stacks. MOQ 300 with Pantone matching and matching capacities available.
Printing and Logo
Screen printing suits solid one- to three-colour marks on TPU and resists abrasion and UV. Heat transfer handles multi-colour artwork. Welded TPU patches give a raised, tonal mark. A logo or card can also be placed behind the clear window, so a brand or event name shows without printing on the body. Trim colours, including the zip stripes and rubber loops, can be matched to brand colours. Artwork is required as vector files; a digital placement proof is returned before sampling.
OEM / ODM Capability
Sealock has manufactured waterproof bags for over 20 years, with factories in Guangdong, China and Ho Chi Minh City, Vietnam — the second site giving brands a non-China origin option where tariff exposure matters. We hold ISO 9001, BSCI, SMETA, Higg, GRS and SCAN certification, and have produced for marine and outdoor brands including Helly Hansen, Musto and West Marine.
The body is high-frequency welded, while the handle webbing and trims are sewn, and sewn construction is an equally mature in-house capability rather than an outsourced step. Most demanding requirements can be met, from a colour and trim change to a set of matching capacities, an airtight zip or a full redesign; complex development with new patterns adds time to the first sample cycle, which is worth planning for early.
Related Products
- Waterproof Duffel Bag 50L – Welded 600D TPU
- Roll-Top Duffel Bag 20L – Welded 500D PVC
- TPU Waterproof Adventure Duffel Bag with Airtight Zipper
- 25L Waterproof Duffel Backpack with 3-Way Carry
- Motorcycle Dry Bag 55L & 68L – Roll-Top Waterproof Duffel
FAQ
What is the minimum order quantity?
300 pieces per colour.
What does it cost?
Price depends on capacity, quantity, fabric, zip type and logo method. Send your specification to info@sealock.com.hk and we will quote within one working day.
Can we put our own logo on it?
Yes. Screen print, heat transfer and welded patches are available, and a logo card can sit behind the clear window. Trim colours can be matched to your brand.
What fits in a 40L duffel bag?
Clothing for a two- to three-day trip, or sports kit with shoes and a towel, or fishing and boating gear for a day on the water. Most 40 L duffels, including this one, fit as airline cabin baggage when not overpacked, but check your airline's size limits.
Is it fully waterproof?
It is rated IPX6: with the zip closed and the end strap buckled, it stays dry in heavy rain and spray. It is not submersible, and the zip is waterproof rather than airtight. An airtight zip is available on custom orders.
What is the strap at the end of the zip for?
It closes over the zip tail and locks it, which keeps water out at the point where zips leak first and stops the slider from opening in transit.
What is the window pocket for?
Items you want to find quickly, such as keys, a phone, travel documents or a name card. The contents show through the clear grid window.
Can it be carried over the shoulder?
Yes. The handles are long enough to sling over one shoulder. A detachable padded shoulder strap can be added on custom orders.
How do I look after the zip?
Rinse off salt and sand after use and lubricate the teeth occasionally with a silicone-based stick. Never force the zip closed over grit.
What is the lead time?
Samples in 7–15 days. Production is 30–35 days after sample approval, from either the China or the Vietnam factory.
Request a Quote
Send your target quantity, capacity, colour and logo artwork to info@sealock.com.hk. We will return a quotation with sample lead time and packaging options.