Heyco Products Materials Information

Type 6/6 nylon is widely used in applications requiring high strength, chemical resistance, and good electrical properties, making it the ideal material for the majority of Heyco's molded products.  The 6/6 means that it is derived from 2 amide-forming ingredients, hexamethylene diamine and adipic acid, each of which contains six carbon atoms.

Standard 6/6 nylon meets UL 94V-2 flammability requirements and is resistant to a wide range of chemical substances including acetone, ammonia, benzene, gasoline, and certain acids.  In addition, flame retardant (UL 94V-0) and high temperature versions of many products are also available.

Nylon has a specific gravity of 1.14 (relative to water at 1).  It is a hygroscopic material, meaning that its' properties are affected by variations in moisture.  The tensile strength and stiffness of a product made of nylon 6/6 increases as the temperature and/or moisture decreases.  When stored at 50% relative humidity and at room temperature, nylon products will maintain their optimum properties.  For that reason, moisture sensitive products are stored in factory sealed bags to preserve their moisture.

RoHS Compliance

After careful evaluation of EU directives on Restriction of Hazardous Substances (RoHS), we certify that all Heyco product lines including conduit, tubing, liquid tight fittings, cordgrips, strain relief bushings, bushings, plugs, wire positioning devices, wire connecting and terminating, and metal stamped products are fully compliant with the following EU directives:

  • 2011/65/EU RoHS (version dated 2011 June 8) Restriction of the use of Certain Hazardous Substances in electrical and electronic equipment (recast)
  • ELV (version dated 2000 September 18), End-of-Life-Vehicle¬† 2000/53/EC
  • WEEE (version dated 2003 January 27, Waste Electrical and Electronic Equipment, Directive 2002/96/EC
  • Directive 2006/122/EC of 12 December 2006 for restriction of Perfluorooctane sulfonates

Additionally none of our products nor our packing materials contain any unconditionally banned substances listed in the table below in concentrations exceeding the Maximum Trace Level (MTL).

Neither our products or our packing materials contain any unconditionally banned, or conditionally banned substances in concentrations exceeding Maximum Trace Level (MTL).

This includes Cadmium (Cd) and its compounds, Lead (Pb) and its compounds, Hexavalent Chromium (Cr) compounds, Mercury (Hg) and its compounds, and prohibited flame retardants, namely Polybrominate Biphenyls (PBBs), Polybrominated Diphenyl Ethers (PBDEs), and Polyfluoroalkyl compounds (PFCs).

Substance Maximum Trace Level
Lead (Pb) 0.1% by weight or 1000 ppm
Mercury (Hg)
Hexavalent Chromium (Cr+6)
Polybrominated Biphenyls (PBB)
Polybrominated Diphenyl Ethers (PBDE)
Cadmium (Cd) 0.01% by weight or 100 ppm
Polyfluoroalkyl Compounds (PFCs) i.e.
* Perfluorooctane sulfonates (PFOS) and
* Perfluorooctanoic acid (PFOA)
0.005% by mass or 50 ppm

Regarding the use of decaBDE, which belongs to the group of polybrominated diphenyl ethers (PBDE's), none of our products contain any banned decaBDE's.


Under REACH, Heyco's products are classified as "articles".  An article in REACH is defined as, "an object which during production is given a special shape, surface, or design which determines its' function to a greater degree than does its' chemical composition".  Currently articles are exempt under REACH.  There are two basic exceptions to the articles exemption, these are:

  • substances that are intentionally released from the article, and
  • substances on the list of Substances of Very High Concern (SVHC).

Heyco is confident that none of the substances in Heyco parts are intentionally released.  Also based on the information provided by their raw material suppliers and their knowledge of the composition of their products, Heyco products do not contain any of the Candidate Substances of Very High Concern (SVHC) as defined by the European Chemicals Agency (ECHA) in article 57 of the REACH regulation.

Key Property data for common materials:
  nylon 6/6 nylon 4/6 Nylon
(Flame Retardant )
Polycarbonate Polyethylene Polypropylene
Characteristic General Use Higher Temp. Halogen Free Transparent Flexible Nonhygroscopic
Specific Gravity 1.14 1.18 1.16 1.20 0.92 0.90
UL Flammability Rating 94V-2 94V-2 94V-0 94V-2 n/a 94HB
Tensile Strength (MPa) 76 65 45 60 13 35
Flexural Strength (MPa) 42 50 70 83   8 53
Heat Deflection (1.8 MPa)   87°C 160°C   79°C 122°C 42°C 104°C
Electrical RTI 125°C 150°C 125°C 125°C 50°C 110°C
All properties are approximate and measured at 50% relative humidity and 23°C (73°F).


Adhesive-backed products are intended for attaching to clean and dry, metal, plastic, glass, paper and painted surfaces.  Not recommended for concrete, bare wood or other porous or irregular surfaces.

Rubber-based adhesive is for general purpose applications.  The majority of items use this type of adhesive.  It provides high initial tack and quickly reaches maximum holding strength.  It will hold under continuous temperatures up to 125°F (52°C).

Acrylic-based adhesive is for greater holding power and/or higher temperature applications, up to continuous temperatures of 185°F (85°C).  It is intended for use with the same clean, dry surfaces as rubber-based adhesive.  Some items are available on special order with the acrylic based adhesive.