Sierra Proto Express is an ISO-9001:2000 and MilSpec MIL-P-55110 certified, Silicon Valley based, high technology printed circuit board manufacturer. We specialize in quick turn prototypes and medium production. We continuously update our capabilities and equipment, such as sophisticated direct imaging machines, enabling us to make reliable and repeatable PCBs down to ... 2 / 2 with an aspect ratio of 15. We regularly make specialty products like Lead-free boards, Burn-in Boards, Polyamide multi-layers, Thermount multi-layers, Metal Core PCBs, carbon paste, and boards with blind/ buried vias, filled vias and micro vias. Our latest offerings include Microelectronics PCBs, down to 1.25 Mils trace and space.