Heavy-duty E-flute, B-flute, and 3-ply corrugated mailer boxes engineered to protect heavy products during transit while delivering a memorable unboxing moment.
Choose from our highly tailored structural variations built specifically to balance aesthetics with maximum product protection.
"Our e-commerce order damage rate dropped to near zero after switching to Pak CustomBox E-flute mailers. The double-wall side construction is rock solid, and the flexographic print quality is outstanding."
Tell us about your box dimensions and quantity to get a custom factory estimate.
Request our free material sample kit to see actual printed textures, foil stamping, and structural folds before committing to a production run.
Direct-to-consumer e-commerce shipping subjects packages to significant drop impacts, high-speed conveyor sorting friction, and extreme warehouse stacking pressure. Standard single-wall RSC shipping boxes frequently crush, dent, or burst along taped seam joints when subjected to these forces. Pak CustomBox manufactures high-compression corrugated mailer boxes using precision flute profiles designed specifically to balance structural rigidity with high-resolution graphic printability.
The structural integrity of a corrugated wall depends entirely on its internal flute geometry. E-flute board (approximately 1.5mm thickness with 90 flutes per foot) offers an ultra-smooth outer surface that is highly receptive to crisp offset graphics, making it the industry standard for premium subscription boxes and lightweight retail kits. Conversely, B-flute board (approximately 3.0mm thickness with 47 flutes per foot) provides significantly superior puncture resistance and stacking strength, making it mandatory for heavier shipments such as electronics, bottled liquids, and footwear.
The most popular structure for e-commerce mailers is the Roll End Tuck Top (RETT) box. This design features non-glued, double-thick corrugated side walls that fold inward, creating a massive perimeter crush barrier that absorbs lateral impact during shipping. The integrated tuck-in lid features front dust flaps that lock securely into the base, eliminating the need for excessive external packing tape and providing a clean, premium unboxing experience for the customer.
A plain brown kraft shipping box is a missed marketing opportunity. We offer full-coverage, double-sided printing, allowing you to maintain a discreet exterior to deter porch theft while surprising the customer with vibrant, full-color brand patterns and typography printed on the interior walls. For large-scale volume production, we utilize high-speed flexographic printing, while premium small-batch runs utilize high-resolution offset lithography laminated directly to the corrugated board (litho-lamination).
E-flute is 1.5mm thick with tightly packed flutes, ideal for high-resolution printing and subscription mailers. B-flute is 3.0mm thick with wider flutes, offering superior puncture resistance for heavier shipping items.
Yes! All our corrugated boxes are manufactured from up to 80% recycled content, utilize water-based flexographic inks, and are 100% curb-side recyclable.
Yes, we offer full-color double-sided printing (inside and outside). Interior printing is highly recommended for maximizing the unboxing visual impact.
Standard Roll End Tuck Top (RETT) mailers fold together securely without glue or tape. However, we recommend a single strip of clear tape or a custom branded tamper-evident sticker to seal the front lip for transit security.
