The LW-31SS-2.50 Hex Bolt is a precision aerospace fastener used in Lycoming aircraft piston engine assemblies. It features a 5/16-18 thread with a 2.50-inch length and is designed for secure mechanical fastening in engine structures and accessories.

The “SS” designation typically indicates stainless steel construction, providing corrosion resistance and durability in engine environments exposed to heat, vibration, and oil.

Its primary functions include:

Securing engine components under high vibration and load
Providing reliable threaded engagement in engine assemblies
Resisting corrosion in harsh operating environments

Bolts like the LW-31SS-2.50 are critical fasteners in aircraft engines, ensuring structural integrity and safe operation of mechanical systems under continuous stress.