We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
White Tyvek expansion envelope with 4.00 inch gusset and self-sealing flap

Quality Park

Quality Park R4497 Tyvek Expansion Envelope 12.00 x 16.00 x 4.00 White 50 Carton

SKU CH-93TD-BWCVJ MPN R4497

A 50-count carton of self-sealing Tyvek expansion envelopes measuring 12.00 by 16.00 inches with a 4.00-inch gusset for bulky mailings

  • TypeBusiness Envelopes
  • FeaturesPuncture Resistant, Tear Resistance, Water Resistant, Moistu
  • ColorWhite
  • Sizes/DimensionsWidth: 12.00" Length: 16.00" Gusset: 4.00" MailerWeight: 18.
  • SpecificationsMailer/Envelope Type: Expansion Closure Type: Self-sealing C
  • Protects bulky mail with 4.00" gusset expansion
  • DuPont Tyvek resists punctures, tears and moisture
  • Self-sealing Flap-Stik closure speeds packing
  • 50 envelopes per carton for high-volume shipping
  • Lightweight 18.00 lb mailer reduces postage cost

Tyvek Expansion Envelope 12 x 16 x 4

This expansion envelope uses heavyweight DuPont Tyvek to protect bulky documents and flat items during transit. The material resists punctures, tears, water and moisture far better than standard paper mailers. It measures 12.00 by 16.00 inches with a 4.00 inch gusset for added capacity. Each carton contains 50 white envelopes.

Self-Sealing Flap-Stik Closure

The open-side design pairs with a peel-and-seal Flap-Stik strip that requires no tape, glue or moisture to activate. This closure speeds up packing workflows and creates a tamper-evident seal once pressed. The adhesive stays reliable across normal shipping temperatures. It removes the need for separate sealing supplies.

Lightweight Bulk Mailing Limits

The Tyvek construction keeps the mailer itself light at 18.00 pounds per 50-count carton, helping control dimensional-weight shipping costs. However, the envelope is intended for items that are not too heavy; dense or sharp-edged loads may stress the seams beyond the material's tear resistance. It replaces boxes only for low-density volume.

Highlights

  • Protects bulky mail with 4.00" gusset expansion
  • DuPont Tyvek resists punctures, tears and moisture
  • Self-sealing Flap-Stik closure speeds packing
  • 50 envelopes per carton for high-volume shipping
  • Lightweight 18.00 lb mailer reduces postage cost

Specifications

TypeBusiness Envelopes
BrandQuality Park
ModelR4497
FeaturesPuncture Resistant, Tear Resistance, Water Resistant, Moisture Resistant, Heavyweight
ColorWhite
Sizes/DimensionsWidth: 12.00"
Length: 16.00"
Gusset: 4.00"
MailerWeight: 18.00 lbs.
SpecificationsMailer/Envelope Type: Expansion
Closure Type: Self-sealing
Closure Side: Open Side
Shipping weight2.72 kg
Package size419 × 373 × 114 mm

Questions about this item

Will the Flap-Stik self-sealing adhesive lose its grip over time and need replacement?

The Flap-Stik closure is a single-use peel-and-seal adhesive; once the envelope is sealed it is not designed to be reopened or resealed, so no ongoing maintenance is required for the adhesive itself.

How much can the 4.00 inch gusset expand before the Tyvek material reaches its limit?

The envelope has a fixed 4.00 inch gusset depth that accommodates bulky items up to that thickness; the heavyweight DuPont Tyvek construction resists punctures and tears at full expansion.

Does the white Tyvek surface reflect enough heat to keep contents cool during all-day transit?

The white Tyvek material is water-resistant and moisture-resistant, but no thermal-reflectivity or temperature-control rating is provided for sustained heat exposure.

Also in this aisle

People compared these

Same shelf, same checkout — eight coins and a 30-minute rate lock.