Mil-spec PCBs

Sierra Proto Express is qualified by the USA Department of Defense to MIL- PRF-55110F for GF (FR4) and GI (Polyimide) Printed Circuit Boards.

Sierra Proto Express has an extended history of manufacturing High Rel printed circuit boards to MIL-PRF-55110 F. We have in-house capability to provide Group A testing that is required for Mil-Spec PCB boards.
Our Mil-spec pcb customers include companies like NASA, Jet Propulsion Labs (JPL), Lockheed Martin, L3 Communications, and Naval Research Labs. 
Call and speak to an Account
Representative about
your order, products and more
1-800-763-7503 x 500

Mil-spec PCB Capabilities

(Capabilities include the following, but are not limited to it. Call us for your special needs!)
  Materials FR4 and Polyimide
  Special Requirements - Copper and Aluminum Metal Core
- Impedance Controlled Boards
- Milling
- Blind vias
- Buried vias
- Filled vias
- Plasma etchback
  Pitch Min .5 mm
  SMT and Through Hole
     Min Line/Space  .003"/.003"
     Surface Mt Pad .008" min
     Layer to Layer Reg +/- .002"
     Max Layers 20
     Min Dielectric .0035"
     Max Thickness .250"
     Overall Thickness +/- 10%
     Bow & Twist  W/SMD .75%
     Bow & Twist  WO/SMD 1.5%
  Drill and Routing
     Hole Location .004"
     Tolerance (PTH) +/- .003"
     Tolerance (NPTH)  +/- .001"
     Min Drill Size  .006"
     Aspect Ratio  16:1
     Min Pad FHS + .014"
     Min Plane Relief  FHS + .025"
     Electroless Nickel 100 u Min, 150 u Max
     Immersion Gold  3 u - 8 u
     Nickel (electroplated) .0003" - .0005"
     Max Gold (electroplated) 100 u
     Solder  coverage and solderable
  Etch Factors
     Inner Layer + .0005"
     Outer Layer  + .0005"
     Controlled Impedance  + 10% (Tighter tolerances down to 5% may be allowed on a per job basis with additional charges)
  Solder Mask
     Min Clearance  .002" /side
     Min Lay Down .004"
     Color  Clear, Black, Red, Blue, White, Purple, etc.
     Min Line .005"
     Color  White, Black, Yellow, etc. 

Call today to speak with an Account Representative at 1-800-763-7503 x 500.
To get a quote submit your gerber files to