S-90385A323 Length 3/4" ASME B18.6.3 Tapping Screws

Key Features & Benefits at a Glance

• Superior plastic retention with DST thread forming design that creates strong, permanent threads without chipping or cracking materials
• Enhanced corrosion resistance through zinc-plated steel construction for extended service life in various environments
• Optimized drive performance with Phillips No. 1 drive providing reliable torque transfer and reduced cam-out risk
• Precision installation with 24 TPI fine threading ensuring secure fastening in plastic assemblies
• Streamlined assembly process using standard No. 44 drill bit (0.086") for proper hole preparation and optimal thread engagement
• Versatile pan head design offering excellent bearing surface and clean aesthetic finish for plastic applications
• Full 3/4" threading providing maximum grip length and holding power throughout the fastener engagement

Professional Applications & Engineering Value

These zinc-plated steel DST thread forming screws are specifically engineered to address common challenges in plastic assembly applications. The unique thread forming action displaces material rather than removing it, creating zero clearance fit that eliminates the need for threaded inserts while providing exceptional resistance to vibration loosening. The fully threaded design ensures consistent clamping force distribution along the entire engagement length, crucial for preventing stress cracking in brittle plastics. With their blunt tip and precise 0.112" thread diameter, these screws guide accurately into pre-drilled holes without material push-out, making them ideal for automated assembly lines. The combination of zinc plating corrosion protection and Phillips drive compatibility makes these fasteners suitable for electronics enclosures, automotive trim components, and consumer products where reliability and appearance matter.

Specification Summary & Compliance

These No. 4 x 3/4" tapping screws feature Class 2A thread tolerances with right-hand threading and comply with ASME B18.6.3 manufacturing specifications. The fasteners are RoHS 3 (2015/863/EU) compliant, ensuring they meet environmental regulations for restricted substances. Manufactured to precise dimensional standards including 0.193" head diameter, 0.071" head height, and 24 TPI thread pitch, these screws maintain consistent performance across production runs. The thread forming (DST) design follows industry-standard tapping methods for plastic materials, requiring No. 44 drill bit (0.086" diameter) for proper installation.