Custom Backpacks: Waterproof and Sewn Packs Built to Your Brand, From 300 Pieces

Sealock makes custom backpacks for outdoor, cycling, travel and lifestyle brands, for retailers building a private-label range, and for companies that want a branded backpack their staff or customers will carry every day. We build them in our own factories in two ways: high-frequency welded waterproof backpacks in TPU or PVC, and sewn backpacks in coated polyester and nylon. Each can be made to your size, colours and design, with your logo. Our minimum order is 300 pieces per style. That fits a product line, a retail programme or a large corporate order; it does not fit a few dozen embroidered gifts or low-cost drawstring giveaways.

This page covers the decisions a buyer makes in order: which construction, what can be customised, which logo methods suit which material, what drives the price and how long an order takes. We have made bags since 2001, over 20 years, at our factories in Dongguan, China and Ho Chi Minh City, Vietnam, and supply soft goods to brands including YETI, OSPREY, Helly Hansen and KAILAS.

Promotional Backpack or Branded Product?

Most searches for custom backpacks are about promotional bags: thin drawstring packs and basic polyester backpacks printed with a logo and handed out at events. They are inexpensive, sold from stock in small quantities, and best bought from a promotional products distributor. A branded backpack is a different job. It is a product people choose to carry for years, on the way to work, on a bike or on a trail, so the brand on it is seen every day. That is what we make: backpacks specified from the fabric up, built to a sample you approve, and tested before they ship.

Waterproof Welded or Sewn?

The construction is the first decision, because it sets the protection, the look, the logo options and the price. A welded backpack is made from TPU-laminated or PVC-coated fabric joined by high-frequency welding, so there are no needle holes in the main compartment. Closed with a roll-top or a waterproof zipper it keeps out heavy rain and spray (IPX6); with an airtight zipper it can be rated IPX7 and survive brief submersion. It suits cycling, commuting in wet climates, paddling, fishing and travel, and it is the construction most of our backpack customers choose.

A sewn backpack is cut from coated polyester or nylon and stitched, with pockets, organisers and padding added more freely than on a welded bag. It is lighter, softer and less expensive, and it takes embroidery and woven labels. With coated fabric and covered zippers it is water-resistant: fine for rain on the way to the office, not for a downpour or a boat. Many brands combine the two: a welded harness of straps and back panel is often sewn, and our sewing lines work to the same quality standard as our welding lines, so a range can include both types from one factory. Our custom waterproof backpack production guide shows how the two processes meet in one bag, and our article on waterproof vs water-resistant backpacks explains the difference for your customers.

What You Can Customise

The fastest route is to start from one of our existing backpacks and change the colours, logo and details. You can also send a sketch, tech pack or reference sample and we will develop a new backpack from the ground up; a new pattern and welding tool add time to sampling. For capacity planning, see our waterproof backpack capacity guide.

Logo Methods, and Which Construction They Suit

On a welded waterproof backpack nothing may be stitched through the sealed shell, so the logo methods are the ones that keep it intact: silk-screen printing for one to three colours, heat transfer for multi-colour artwork, a welded TPU or PVC logo patch for a raised mark, embossing, reflective printing for cycling packs, and a branded zipper pull or buckle. Woven labels and patches can be sewn onto the harness, which sits outside the waterproof compartment.

On a sewn backpack every method is available, including embroidery, woven labels, rubber and silicone patches, and printing. Send artwork as a vector file with Pantone references and tell us where it should go. Our guide to logo methods on waterproof bags compares how each one wears.

MOQ, Sampling and Lead Time

MOQ is 300 pieces per style, with colours usually split within one order; a few models start at 500. Samples take about 7–15 days for a backpack based on an existing model; a new design takes longer. Bulk production takes about 30–45 days after the sample is approved, and up to 60 days for complex designs or peak-season orders. Production can be placed in China or in Vietnam, which gives buyers a choice of origin when planning for tariffs. For fewer than 300 pieces, a promotional products distributor that decorates stock backpacks is the better route.

What Drives the Price

Construction is the biggest factor: a welded waterproof backpack costs more than a sewn one of the same size, and an airtight zipper adds more again. Then come the fabric, the size, the harness and back system, the number of pockets and the laptop sleeve, the logo method and number of colours, the packaging and the quantity. New tooling or a new pattern is charged once. For a quotation, send us the use, size, construction, artwork, quantity and target price.

Base Models You Can Customise

Image	Model	Capacity	Dimensions (H × W × D)	Weight	Construction	Use
	Waterproof Laptop & Travel Backpack 22L	20–22 L usable	50 × 29 × 16 cm (19.7 × 11.4 × 6.3 in)	About 0.9 kg (2.0 lb)	TPU-coated fabric, high-frequency welded; airtight zipper under a laminated flap; 15.6″ laptop compartment	Commuting and business travel
	SL-E641 25L Airtight-Zipper Backpack	25 L	54 × 27.5 × 16.5 cm (21.3 × 10.8 × 6.5 in)	1.0 kg (2.2 lb)	TPU laminate, high-frequency welded; curved airtight zipper; IPX7	City and outdoor, minimalist look
	SL-E986 20L Roll-Top Waterproof Backpack	20 L	50 × 26 × 16 cm rolled (19.7 × 10.2 × 6.3 in)	0.75 kg (1.7 lb)	420D TPU, high-frequency welded with reinforced stitching at stress points; roll-top; IPX6	Cycling and commuting; 15.6″ laptop sleeve
	SL-C261 Waterproof Duffel Backpack	25 L	26 × 48 × 26 cm (10.2 × 18.9 × 10.2 in)	1.35 kg (3.0 lb)	TPU-laminated 420D nylon, high-frequency welded; airtight main zip; IPX7	Travel and water sports; three-way carry
	SL-E1314 8L Waterproof Sling	8 L	37.5 × 25 × 12.5 cm (14.8 × 9.8 × 4.9 in)	0.65 kg (1.4 lb)	TPU-laminated fabric, high-frequency welded; waterproof zipper; IPX6	Light everyday and outdoor carry

See the full waterproof backpack range. For day-use packs, see our guide to the waterproof daypack; for production detail, our OEM waterproof backpack supplier guide; and for duffels in the same range, our guide to custom duffle bags.

How We Control Quality

Every order passes through IQC on incoming fabric, zippers, buckles, foam and webbing, IPQC during welding, sewing and assembly, and OQC on finished backpacks, with SGS or QIMA third-party inspection available on request. Welded seams are tested for bonding strength and sewn seams for tensile strength, with attention to the shoulder strap anchors and the base, where a loaded backpack puts the most stress. Straps, grab handles and buckles go through a load test of 1,500+ cycles, and zippers are opened and closed 3,000 times. Hardware is tested in salt spray, fabric for abrasion, and colour fastness and colour difference are checked against the approved sample so brand colours stay consistent across the order. IPX7 backpacks are verified with a full water-immersion test of 2+ hours and IPX6 backpacks with a heavy rain and water-jet test.

Frequently Asked Questions

What is the minimum order for custom backpacks?

300 pieces per style, with colours usually split within one order. A few models start at 500.

How much do custom backpacks cost?

The price depends on construction, fabric, size, harness, pockets, logo method and quantity. A welded waterproof backpack costs more than a sewn one. Send us your specification, artwork and quantity for a quotation.

Can you embroider our logo on a waterproof backpack?

Not on the sealed body, because embroidery would pierce it. We print, heat-transfer, weld or emboss the logo instead, and can add embroidered or woven labels to the harness.

Do you make drawstring or promotional backpacks?

We focus on branded backpacks made to be used for years. For low-cost drawstring giveaways in small quantities, a promotional products distributor is the better fit.

How long does a custom backpack order take?

About 7–15 days for samples and 30–45 days for bulk production after approval, or up to 60 days for a complex new design.

Can you make a backpack from our own design?

Yes. Send a sketch, tech pack or reference sample. A new design needs new patterns or welding tools and a longer sampling stage.

Start Your Custom Backpack Order

Send us the use, size, construction, logo artwork and quantity, and we will reply with a recommendation and a quotation, then make samples and plan production in China or Vietnam. Contact us at info@sealock.com.hk or call +86-769-82009361.