There are those who think all cables are created equal. Well, they're not.

Temperature extremes to which Flexx-Sil outer jackets can be exposed.

The simplicity of flat cable with its parallel conductor geometry eliminates many of the common sources of wiring error and malfunction. Registration of the conductors is one-to-one with the terminating connector or board so that proper contact assignment is almost automatic.

The use of flat cable often eliminates much of the conventional wire weight. Such things as redundant insulating materials, fillers and tapes are not required. In addition, the composite flat cable construction is so mechanically strong that it is not necessary to have large conductors for strength. The copper cross-section can thus be reduced to what's required to carry the current load or to satisfy voltage drop requirements. Strength is enhanced by the fact that all conductors and insulation equally share tensile load.

Extruded flat cables can be made in conductor sizes from 4/0 AWG to 44 AWG, single extrusion widths of up to 4 inches and cable heights of 1 inch, plus they can be utilized in continuous operating temperatures of -65°C to +260°C.

Since they are extruded, flat cables are available in continuous lengths, cut to order, prepped for termination or as assemblies with just about any circular or rectangular connector, including Mil-DTL-38999, Solder Tab Nano, Micro-D, Ethernet, IDC, Hermetically Sealed, Lugs and custom connectors and PCB components. Assemblies can be soldered, crimped, potted and over-molded.

To design a custom cable, space restrictions, bend radius, environmental issues, application specifics, and mechanical, electrical and vacuum requirements are needed.

It's All About the Wire

Cicoil's patented computer-controlled extrusion process.

Today, most wire utilized in cables is made up of multiple base wire strands, rather than being made of a solid piece of metal/wire. Multiple strands make the wire more flexible, allowing it to bend and flex more easily than solid wire.

The finer the base strand, the more flexible the wire. Standard 24 AWG wire has 7 base strands, ‘flexible’ wire has 19 base strands, while Cicoil High-Flex wire utilizes 66 base strands. All Cicoil wire has base stranding of 40 AWG minimum, versus 36 AWG and larger in other ‘flexible’ wires. Cicoil wire conductors have two to three times more base strands than conventional ‘flexible’ wire, which makes them extremely flexible. Wires with smaller base stranding will have a much smaller bend radius than wires with larger stranding. In addition, finer stranded wire has significantly longer life in flexing applications, as bending stresses are distributed across many more wire strands, thereby dissipating the strain on the overall conductor.

The copper cross-section can thus be reduced to what's required to carry the current load or to satisfy voltage drop requirements. Strength is enhanced by the fact that all conductors and insulation equally share tensile loads.


The outer jacket on Cicoil's cables is made with a propriety material called, Flexx-Sil™, which is designed for high-flex, high-performance, and even high-voltage applications. This unique material combines the best aspects of silicone rubber, such as flexibility and extreme temperature exposure.

Standard silicone has been known to outgas harmful materials when utilized in high-vacuum environments. As a result, contaminates from within the silicone material are released and then condense onto highly sensitive electronics, circuit boards, optics, etc…

Crystal-clear, Flexx-Sil™ rubber has zero additives, does not oxidize or outgas harmful contaminants, and is Space Flight Approved by NASA. The ultra-pure cable is halogen-free, Class 1 Clean Room Rated and exceeds ASTM E-595 outgassing specifications for vacuum and Space use requirements.

Unlike, PTFE or Polyurethane jacketed cables, Cicoil's extrusion process separately encases each individual inner component, which prevents wires from rubbing against each other and creeping out when exposed to severe vibration, shock and turbulent flight conditions. Where other materials require conduit or “armor” for protection, the encapsulated design does not. In addition, the jacket is self-healing from small punctures and can easily be repaired in the field, whereas other cable types have to be discarded.

The Crystal-Clear Jacket also allows for quick, easy and safe inspection of cables in just about any application. Unlike cables infused with color additives and possible contaminants, the Flexx-Sil™ rubber design offers complete transparency, so you won't need to be concerned about what's under the jacket.

Patented Extrusion Process

Unlike the standard, open-floor extrusion line process utilized in the electrical cable industry, Cicoil utilizes a patented computer-controlled extrusion process, which allows individual components to be placed in a flat profile, precisely controlling the spacing of each component, insulation thickness and the overall cable shape. The thickness of the extruded flat cable is precisely controlled to within 0.005”, and conductor spacing accuracy to within 0.002”.

Conventional flat cable molding process.
Cutting conventional flat cables out of the mold.

The solid one-piece construction can be made in unlimited lengths and the cables can combine power conductors and twisted shielded pairs, in different AWG sizes and various diameters, all combined in a single flat profile. Other components, such as tubing, fiber optics, mounting strips, coax conductors, thermocouple cable, and strength members can also be integrated into the cable design.

Lastly, all cables are cured continuously, with no debris, humidity or material contamination in an automated, climate controlled operating environment. This manufacturing process is a unique, one-of-a kind operation.

Extruded Flat Cables vs Molded Flat Cables

Flat molded cables may look similar to Extruded Flat Cables from a distance, but once you take a closer look, the similarities no longer apply.

In the molding process, wires are stretched between pins in a metallic mold that typically ranges from 1 to 6 feet in length. Liquid silicone and chemical curing agents are poured over the wires, and once settled, additional silicone is poured to attain proper cable thickness. The cable will need to fully cure over another 2-3 days.

Unlike the ultra-clean manufacturing process of extruded flat cables, molded flat cables are exposed to contamination by dust, metal chips and airborne debris during the pouring and curing processes.

After the curing process is complete, the cable needs to be cut out of the mold with an X-ACTO knife, leaving numerous holes from the pins and sharp edges, which will impede overall cable strength and flexibility. As a result, the pin holes need to be filled in by hand with silicone, and the cable has to be cured again. In addition, excess flash needs to be removed from the cable jacket by hand with sharp blades as well.

Since it is a manual process, the “poured” method results in varied component spacing and inconsistent cable thickness with each batch of cable produced. The odds of receiving a duplication of identical flat cables is almost impossible. Complex designs and variations in profile, such as hybrid cables with different AWG sizes and tubing, can't be combined into a single flat cable.

Gravity causes molded cables to be thicker at the bottom and thinner at the top, which will cause cable failure as a result of wire breakage through the thin cable top, especially in flexing applications

Extruded flat cables have rounded radiuses on each end, making them mechanically stronger and more flexible than molded flat cables. Utilizing a computer controlled extrusion process, any outside cable profile can be created as the application requires, so the same exact cable will be produced the same way every time.