Established in 2002, KnownPCB is a manufacturer and service provider for export of Various Printed Circuit Boards, specialize in Small-lot to Medium-lot and support Quick-turn prototype service for our global customers. Buyers from international markets choose to source from us because of our high production capacity and high product development capabilities. Our specification of products and features includes: Number of layer: 1, 2, 4 or 6, up to 32 layers Board type: rigid, flexible, rigid-flexible, HDI，Aluminum Board material: FR-4 glass epoxy, FR-4 high TG, RoHS compliant, Halogen free, aluminum, Rogers and more Board thickness: 2 layer :0.1mm-3.2mm;Multilayer:0.4mm-3.4mm;Flex: 0.01-0.25mm Copper thickness: 0.5~12oz Solder mask: Single or double-sided green, also support red, white, yellow, blue, black Silkscreen: double-sided or single-sided in white, yellow, black or others Surface finishing: HASL lead free, Immersion Gold, Nickel , Immersion Tin, Immersion Silver, OSP，Gold Finger, Peelable Mask, Carbon Ink and more The min. line width/line clearance: 4mil/4mil The min. hole diameter:0.1mm Copper thickness in hole wall:≥18um.(We can meet 25um and 18um is guaranted.)