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3M™ Dual Lock™ Reclosable Fastener SJ3550 250 Black, 1 in x 50 yd 0.22 in (5.6 mm), 2 per case Bulk

3M ID  70070521102    UPC#  00021200743795    Part Number  SJ3550    3M Product Number  SJ3550     
3M™ Dual Lock™ Reclosable Fastener
3M™ Dual Lock™ Reclosable Fastener
3M Dual Lock Reclosable Fastener 250 Stems Per Inch Black
3M™ Dual Lock™ Reclosable Fastener
3M(TM) Dual Lock(TM) SJ4580 Stem Close Up
3M™ Dual Lock™ Reclosable Fastener SJ3550 gives you up to five times the strength of hook-and-loop fasteners. As tough, polyolefin mushroom-shaped stems snap together, they provide both the tensile strength to replace traditional fasteners and a cleaner looking result. Our remarkable fasteners can be opened and closed over and over, up to 1000 times for repeated access or repositioning.
  • Reclosable system is up to five times stronger than typical hook-and-loop fasteners
  • Snap-in-place installation replaces screws and nails, snaps, and rivets
  • Black fastener is hidden when closed and provides clean, smooth appearance
  • Acrylic adhesive bonds well to metals, glass, paint, and high surface energy plastics
  • Ideal for indoor and outdoor use to attach doors, access panels, cushions, headliners, signs and display components
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The mushroom heads easily slide over each other allowing positioning of parts before they are snapped together to create a firm fastening attachment. When mated, the black fasteners are hidden from view and leave you with an unbroken surface to help create a smooth, clean appearance. We use a pressure-sensitive, acrylic adhesive to provide high adhesion for indoor and outdoor applications that adheres well to metals, glass, and high surface energy plastics such as acrylic, polycarbonate, and ABS.

The 3M(TM) Dual Lock™ SJ3550 Reclosable Fastener is a "Type 250," which means its surface has approximately 250 stems per square inch with a 0.23 inch engaged thickness. We manufacture the stems and heads from black polypropylene and the backing is made of 37 mils of acrylic foam tape protected by a removable liner. This construction allows for better contact with surfaces having slight texturing or surface irregularities.

To gain various levels of holding power, this fastener can be mated with different 3M Dual Lock Reclosable Fastener types. Suggested combinations of mated fasteners are:

  • Type 250 to Type 170
  • Type 250 to Type 250
  • Type 170 to Type 400
  • Type 250 to Type 400
  • For a quick grab attachment with high strength but limited cycle life any of our 3M Dual Lock products can be mated with 3M™ Hook and Loop Reclosable Fasteners.
  • How it works:
    When two pieces of 3M Dual Lock Reclosable Fastener are pressed together, the stems flex and the mushroom heads slide past each other. After passing the mushroom heads on the opposing mating piece, a stem snaps up into its original position, interlocking with the opposing heads. Listen for the audible snap to signal that the fastener is engaged. The attachment formed may be as effective as screws or rivets, but will peel apart for repositioning. 3M Dual Lock reclosable fasteners are used extensively in transportation, electronics, business equipment, machinery, medical, and sign and display markets. Applications include attaching signs, enclosure panels, banners, repositionable shelving, vehicle ceiling panels, furniture seats and backs, marine carpeting, and orthopedic brace closures. Today, you expect more options to secure, attach and connect surfaces. 3M Dual Lock Reclosable Fasteners offer instant installation and high-strength attachment, yet can be opened as easily as zippers. That functional flexibility, as well as superior aesthetics, reduced weight, and savings in labor and installation costs, make our innovative fasteners a popular and effective solution.


    Adhesive TypeGeneral Purpose Acrylic Adhesive
    ApplicationsWall Panel Attachment, Wall Headliner Attachment, Attaching City Bus light fixtures, Privacy Curtain Rail Attaching, Ceiling Attachment, Sunroof Trim Attachment
    BrandDual Lock
    Closure Life1000
    Engaged Thickness0.23 Inch
    Flame RetardantNo
    IndustriesTransportation, Specialty Vehicle, Construction, Automotive, Furniture, Medical, Military & Government, General Industrial, Retail, MRO, Electronics, Packaging
    Length50 Linear Yard
    Length (Metric)45.72 m
    Liner Thickness4 mil
    Liner TypeClear Polyolefin
    Low ProfileNo
    Maximum Operating Temperature (Celsius)93 Degree Celsius
    Maximum Operating Temperature (Fahrenheit)200 Degree Fahrenheit
    Product FamilyCollage and assemblage
    Product FormRoll
    Product LineAdhesives, sealants and coatings
    Stem Density250
    Width1 Inch
    Width (Metric)25.4 mm