The MEMBRANE sil line was developed with one goal in mind - create the lightest, most waterproof fabrics on the market. Same silpoly benefits of lower water absorption and increased UV resistance, but in a waterproof textile that's 15-30% lighter than traditional lightweight coated nylon/polyester fabrics. MEMBRANE Silpoly PU4000 is the high water resistance version of our MEMBRANE silpoly line of ultralight coated materials. To achieve high water resistance with low-stretch, the material features the following: 15D polyester plain-weave construction High-quality sil/PU coating on one side and multi-pass PU4000 coating on the other MEMBRANE Silpoly PU4000 is best for situations where you want to save weight, but still have the highest water resistance possible. The PU4000 coating also allows seams to be taped and reduces bias stretch making the material somewhat easier to sew. A premium material for all projects requiring an extremely lightweight, waterproof textile. Common applications include tarps* (see note below), ponchos, gear sacks, pack covers, etc. *Note - If using for a tarp, please keep in mind that this material pushes the limit on weight, waterproofness, and durability. We do not recommend use outside of relatively low-stress applications. *This fabric has distinct shiny (PU4000) and matte (sil/PU) sides. It is recommended to put the matte side facing out and shiny side facing inwards. If seam sealing, we recommend using a PU sealant such as Seam-Grip on the PU4000 side of the fabric. Want to quickly compare all our lightweight coated/non-breathable fabrics? Check out the "Fabric Comparison Guides" on our FAQ page. Details/Specs Product Details Colors Olive Yellow (N/A), Black (N/A), Charcoal Gray (18-0601), Dark Olive (19-0516), Khaki (16-0726), Black (N/A), Olive Drab (18-0622), Blaze Yellow (12-0643), Crimson (19-1762), Royal Blue (19-4245), Deep Purple (N/A), Robin Egg Blue (3248) Panton ref # N/A Width 58-59" usable, selvedge trimmed Weight 1.07 oz/yd2 finished weight Denier 15D Finish/Coating Sil/PU one side, multi-pass PU4000 other side Ordering/shipping info Ordering/Shipping order-change-title order-change-desc cont-cut-policy-title cont-cut-policy-desc Shipping Availability USA and International Shipping Method/Rates shipping-summary Estimated Delivery Date estimated-delivery Samples sample-redirect