Toughness Test Pull hard, not easy to break Focus Ls More Professional Through the selection of high-quality new materials and processtechnology improvement and upgrading. Zoom In On The Details Smooth surface, no particle sense, good gloss,therebyreducing friction damage. The Production Workshop Packing & Shipping Advantages : Sturdy & Durable Construction: Our plastic mailing envelopes are made with premium-grade virgin Polyethylene plastic which are tear-resistant, puncture-resistant and waterproof. And every mailer is equipped with tamper-proof strong self-sealing adhesive strips.You can rely on our postal bags to withstand various factors and ensure that your package is safe before it reaches its destination. 2.New formula white express bagRaw material: new formula PEmaterialThickness: normal, thickened Surface: Smooth Color. white matte Specification (W xL + Sealing):17X25+4cm, 20X28+4cm, .25X34+5cm.28X36+4cm.32x40+4cm.38x46+4cm, 42X50+4cm, 45X55+4cm 3.Economy grey express bagRaw material: primary recycled materialThickness: normal, thickened Surface: Smooth Color: matte grey Specification (Wx L+ Sealing): 17X25+4cm, 20X28+4cm, 25X34+5cm.28x36+4cm. 32x40+4cm. 38x46+4cm, 42×50+4cm.45X55+4cm.47x58+4cm, 55x65+4cm.60x80+5cm Can be customizedThick express bag with new materialRaw material: new PE material Thickness: thickened Surface: smoothColor: white light Specification (W x L + Sealing):17X25+4cm, 20X28+4cm, 25X34+5cm.28X37+5cm.32X40+4cm.38x47+5cm, 42×50+4cm, 45X55+4cm.47x58+4cm, 55x65+4cm.60x80+5cm