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June, 2014
3M™ Dual Lock™ Reclosable Fastener SJ3560
Product Description
3M™ Dual Lock™ Reclosable Fasteners are positive locking, hidden fasteners designed for use in a variety of
attachment solutions. They consist of continuous strips of polyoleꢀn stems with a mushroom shaped top
protruding up from the backing. When snapped together the mushroom shaped caps interlock producing a
strong reliable Fastener.
The standard Dual Lock fasteners are available in three diꢁerent stem densities (170, 250 and 400) referring to
the approximate number of stems per square inch. (26, 39, 62 stems per square centimeter) By inter-locking
diꢁerent stem density combinations you can create the strength that suits your application; more total stems
give higher strength. The Dual Lock Reclosable fasteners can be mated in the following combinations of
increasing closure strength: Type 170 to Type 250, Type 170 to Type 400, Type 250 to Type 250 and Type
250 to Type 400. We do not recommend using the Type 170 to 170 because it does not have enough strength
for a good connection. We do not recommend using the Type 400 to 400 because it is too strong and may
cause stems and heads to rip out rendering the fastener no longer reclosable.
The Dual Lock Low Proꢀle has one stem density of approximately 705 stems per square inch and they
interlock to themselves. The low proꢀle products are not intended to mate to the standard size Dual Lock.
There are a variety of pressure sensitive adhesives available with Dual Lock to cover most application needs.
The pressure sensitive adhesive makes the Dual Lock easy to use, simply remove the liner, place the Dual Lock
and apply ꢀrm consistent pressure to assure good contact with the substrate you are adhering. We also oꢁer
non-adhesive backed Dual Lock for applications where the PSA does not meet your needs.
Product Features
•Easy Alignment: Dual Lock fasteners engage in any direction or position. The mushroom stems slide into
position until they are engaged by snapping together applying ꢀrm pressure, this eliminates concerns about
misalignment or spontaneous engagement.
•Positive Locking: Dual Lock fasteners engage/fasten with an audible snap and detectable movement assuring
complete and secure closure.
•Reclosability: Dual Lock fasteners can be opened and closed for multiple closure applications (high cycle
life).
•Blind Attachment: Dual Lock fasteners can be attached on the backside of substrate (i.e. trim piece) where it
will not interrupt the show surface.
•Rattle-Free: Dual Lock fasteners will not rattle loose.
•Ease of Assembly: Dual Lock fasteners can be used to attach components before they enter the ꢀnal
assembly plant, reducing the number of parts and the assembly time. No tools are required.
•Adjustable Strength: By selecting diꢁerent combinations of the various stem densities of the Dual Lock the
fastener can be designed to meet the strength needs of the designer.
•Product Forms: Dual Lock fasteners come in a variety of forms: Backed with Pressure Sensitive adhesive,
Non-woven, Rigid backed, Die Cut Shapes, and low proꢀle.
•Attachment Methods: The wide varieties of Dual Lock fasteners allow a design engineer ꢂexibility to be able
use and attach Dual Lock to just about any substrate or application. Peel and stick pressure sensitive adhesive
backed is quick and easy yet strong and secure. Non-woven backed can be used with a variety of adhesive
choices such as hot melt, liquid, epoxies, sealants, etc. We have parts that can be attached with a screw or
rivet; rigid and plain backed for developing your own special device.