Poly mailers are some of the most commonly used packaging materials in the United States. These lightweight, durable, and flexible plastic envelopes help companies save heaps of money on shipping, storage, and delivery expenses. However, while the standard poly mailer is durable, it is not cushioned. Non-fragile items like clothing will be just fine inside a poly mailer, but semi-fragile items like jewelry and electronics need extra protection as they go through the rigors of shipping and storage.

If you need to ship semi-fragile products and you want to avoid the high shipping costs of boxes, ship these products in a bubble mailer! Bubble mailers feature an inner lining of bubble wrap that provides extra cushion and protection for your goods. These specialty mailing envelopes come in two main types: kraft bubble mailers and poly bubble mailers. While these two kinds of mailers share many similarities, they also have some key differences that set them apart from each other. In this article, we will explore the differences between these mailers and recommended uses for each type.

Material

Kraft bubble mailers are made from kraft paper, a high-strength brown paper formed from chemically-treated wood pulp. The pulp is screened, rolled out, dried, and cut up into individual rolls of paper; this is the same material as paper grocery bags. Kraft mailers are rigid and lie flat, making them ideal for books, gift certificates, magazines, and other flat items that need to be protected from flexing and bending.

Poly bubble mailers are made from polyethylene, a popular and versatile plastic material. This plastic can be shaped and molded into a wide range of forms and functions. Polyethylene is light, yet durable and flexible. Poly mailers lay flat when empty, but can easily conform to the shape of the object held inside. These mailers are recommended for packing non-fragile and/or irregularly shaped items like clothing.

Color

Kraft bubble mailers have a look that people describe as “natural” or “rustic”. Many kraft mailers are available in kraft paper yellow. However, adding bleach to the manufacturing of kraft paper can produce white paper; white kraft paper has a professional appearance, while yellow kraft paper is a more eco-friendly option.

Poly bubble mailers are exclusively available in white. While poly mailers may lack the “natural” look of kraft mailers, they are much more conducive for branding. Companies can print branding information all over the blank, white mailer. On top of this, white poly mailers have a “clean” and “modern” look that has a unique appeal and works well with the latest electronics, art pieces, and clothing.

Closure

Both kinds of bubble mailer feature an adhesive strip on the flap of the envelope. Users simply peel away the plastic and seal the mailer with light pressure. Not only does this adhesive strip save people money that would otherwise be spent on tape, but it also acts as a tamper-evident seal. Thieves and vandals will find it nearly impossible to open these mailers without leaving behind signs of pilferage.

Durability

Kraft paper is strong and resistant to tearing; “kraft” is the German word for strength, after all. As previously mentioned, kraft bubble mailers are flat and rigid, keeping items protected from shifting and handling while in transit. Compared to poly mailers, kraft mailers have larger, taller bubbles in their inner bubble lining; this means that kraft bubble mailers offer greater protection than poly bubble mailers.

However, kraft mailers have a major weakness: moisture. Simply put, paper and water do not mix. While kraft mailers may last a couple of minutes in high-humidity environments, they will quickly deteriorate with enough time and moisture.

Poly bubble mailers may not have the same rigid strength as their kraft counterparts, but they are durable and 100% waterproof. In environments with high humidity or excess moisture, poly mailers will keep your goods nice and dry.

Despite this, the bubbles inside a poly mailer are smaller and shorter when compared to kraft mailers. So while poly bubble mailers may perform well in extreme environments, kraft mailers offer more material protection.

Recyclability

Kraft bubble mailers are 100% recyclable, but they’re not the most convenient to recycle. Paper and plastic are recycled separately, so kraft mailers need to have the kraft envelope and inner plastic bubble wrap separated from each other before they can be recycled.

Poly bubble mailers are also 100% recyclable and are much easier to deal with. Since both the outer envelope and inner bubble lining are plastic, they do not need to be separated upon disposal. Simply toss your poly bubble mailer into the recycling bin and you’re good to go!

Final Thoughts

We’ve compared kraft bubble mailers and poly bubble mailers side-by-side. Kraft mailers are rigid and look “natural”, making them ideal for shipments that cannot be bent or flexed; however, kraft mailers can be weakened in the presence of moisture. Poly mailers are flexible, waterproof, and look “modern”, making them ideal for shipping non-fragile goods. For more comparisons between kraft and poly bubble mailers, as well as breakdowns of the most popular bubble mailer brands, take a look at this Small Business Trends article exploring popular bubble mailers.

Bubble mailers don’t stop with just kraft and poly. Glamour bubble mailers are colorful and stylish, offering both protection and a visually appealing outer packaging. If you’re curious to learn more, check out our article on glamour mailers and why they’re great for branding and sending special deliveries.

At PackagingSuppliesByMail, we offer a wide selection of mailing envelopes, including kraft and poly bubble mailers. On top of this, we offer free shipping for all bulk orders of our mailers. So if you’re interested in increasing protection and reducing costs for your shipments, consider shipping with poly mailers.