Apex HC-100-5/16 Female Spline Socket 3/8 Drive Sae

Product Description

The APEX HC-100-5/16 is a female spline socket designed for 3/8 inch square drive applications requiring a 5/16 inch spline fit. Built for SAE fastener work, this specialty socket measures 1.5 inches in overall length and is suited for use in tight or recessed fastener locations where a standard socket will not engage. The female square drive configuration makes it a go-to tool for technicians working on equipment with internal spline fasteners. At 0.05 pounds, it is lightweight enough for overhead or confined-space work without adding fatigue.

This socket is used across HVAC, refrigeration, plumbing, and general mechanical service wherever internal spline fasteners appear on equipment panels, access covers, valve bodies, or mechanical assemblies. The 3/8 inch drive size is compatible with standard 3/8 inch ratchets, extensions, and torque wrenches, making it easy to integrate into an existing tool setup without adapters. Techs working on commercial or residential mechanical systems will find this useful when factory-installed spline fasteners are encountered during service, replacement, or retrofit work.

Key Features

• Female square spline drive design engages internal spline fasteners directly
• 3/8 inch drive fits standard ratchets, extensions, and torque wrenches
• 5/16 inch spline size for SAE fastener applications
• 1.5 inch overall length suits recessed and confined fastener access
• Lightweight at 0.05 pounds for reduced fatigue during overhead work
• SAE specification for use with inch-based fastener systems

Compatibility

Designed as an OEM-style specialty socket for use with 3/8 inch square drive tools on SAE internal spline fasteners measuring 5/16 inch.

Installation Notes

This socket is installed by mechanical technicians and service professionals using standard 3/8 inch drive ratchets or torque wrenches. Always de-energize and lock out equipment before accessing fastened panels or covers. Confirm the spline size matches the fastener before applying torque to avoid rounding the drive. Do not use impact drivers unless the socket is rated for impact use.