SEMI-FLEX is a flex-rigid PCB,Website:http://www.unioncircuits.com, typically 4 layers, made entirely of FR4. Unlike conventional flex-rigid PCBs, the flexing element is not polyimide but a thin FR4 core with two layers of copper specially treated to flex without cracking. A less robust solution uses a depth-milled layer rather than a core.Key Specification   Layer Count4MaterialFR-4(Tg130), FR-4(Tg170)Finished Thickness1.6~3.2mmFinished Outer Cu Thickness1OZ, 2OZFinished Inner Cu ThicknessHOZ, 1OZ, 2OZSurface FinishImmersion Gold, OSPSoldermaskGreen/ White/ BlackSilkscreenWhite, BlackPanel Size250x720mm(max)Attention: "These are the basic specifications we gonna to need for your Printed Circuit Board fabrication, if you need a quick quote or going to order soon, to save time please kindly provide all the fabrication details to us, of course if there were any other special requirements or details out of this specification, please also comment so we can consider it in our quotation."           --From Union Circuits Engineering dept.Product DetailsMOQ1 PieceProduction Lead Time5~15 Working Days Quick turn, 10~20 Working Days mass productionMin. Drill Hole Size0.2mmMin. Trace Width/Spacing4/4milData FormatGerber RS-274-D/X, .pcb, .pcbdoc, .cam, ODB++, CADE-Test100% E-test(cost included in the Unit Price, NO extra charge)CertificationsUL, CUL, ISO9000, ISO14001, TS16949.StandardIPC-6013 Class 2(default), Class 3 (base on request)ApplicationAutomotive, Cellphone, computer, printer, communication equipment, camera…PackingInner vacuum + foam, Outer carton boxShippingDHL(default), UPS, TNT, FedEx, EXW, FCA/FOB HongKong, By SeaPaymentT/T, PayPal, Western Union (USD, EUR)