New PEM® Reelfast® Surface Mount Spring-Loaded Captive Panel Screws Install Precisely and Permanently where Designed on Printed Circuit Boards

New PEM® ReelFast® surface mount spring-loaded captive panel screws (Type SMTPFLSM™) from PennEngineering® install precisely and permanently where designed on printed circuit boards to provide secure attachment and allow for subsequent access whenever necessary.  These all-metal captive screw assemblies mount in one piece on boards using the pick-and-place method and will install in the same manner and at the same time as other surface mount components prior to the automated reflow solder process.  The captive screw technology eliminates issues and risks associated with the handling, installing, and potential loosening of standard screws and can be easily actuated with the combination Torx®/slot drive.

PEM Type SMTPFLSM captive panel screws are supplied on tape and reel conforming to industry standards and are compatible with existing SMT automated installation equipment.  A polyimide patch affixed to the end of the fastener allows for vacuum pickup.  Unlike conventional fasteners, there is no requirement for secondary installation operations, which typically can damage boards and create scrap.   An anti-cross thread feature serves to correct off-angle installations and prevent thread damage during the mounting process.

The fasteners install reliably in boards of any hardness as thin as .063” / 1.6mm.  They are available in thread sizes #4-40 through #6-32 and M3 through M3.5 and in multiple screw lengths. Depending on length, the captive screw is designed to retract flush in the up position.

These captive panel screws join a growing portfolio of PEM surface mount fastener solutions engineered to perform a wide range of attachment functions in printed circuit board applications.

Detailed specifications, fastener drawings and models, and performance data (Bulletin SMTPF) for the RoHS-compliant fasteners can be accessed at