We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
100 black oxide alloy steel socket head cap screws 5/16-18 x 2.25 inch hex drive

Kerr Lakeside

Kerr Lakeside 31C225KCS 5/16-18 x 2.25in Socket Head Cap Screw 100pcs

SKU CH-3A7K-42Q27

A pack of 100 alloy-steel socket-head cap screws with a 5/16-18 UNC thread, 2.25 in length, black-oxide finish and 1/4 in hex drive

  • Product typeSocket
  • Main materialHAWA
  • Alloy steel construction provides high tensile strength
  • Black oxide finish resists corrosion and wear
  • Hex socket drive allows secure installation with 1/4 in key
  • UNC coarse threads ensure reliable grip in standard holes
  • 100-piece pack supplies enough fasteners for large projects

Socket head cap screw for inch-system assemblies

The Kerr Lakeside 31C225KCS is a 5/16-18 UNC socket head cap screw made from alloy steel with a black oxide finish. Each fastener measures 2.25 inches in length and features a 1/4 inch hex socket drive. The thread is partially threaded with a minimum thread length of 1 3/8 inches. This 100-piece pack suits maintenance, fabrication and machine assembly tasks that require inch-series fasteners.

Alloy steel construction handles clamping loads

The alloy steel body provides the strength expected of a standard socket head cap screw under typical clamping forces. Black oxide finish adds mild corrosion resistance and reduces light reflection. The cylindrical head height ranges from .306 to .312 inches, allowing the fastener to seat flush in counterbored holes. No lubrication or special surface treatment is specified for standard installation.

1/4 inch hex drive fits common hex keys and bits

Installation requires a 1/4 inch hex driver or bit, a size widely available in inch and metric tool sets. The right-hand UNC coarse thread engages standard 5/16-18 nuts and tapped holes. Partially threaded shank leaves an unthreaded grip length for alignment or shear resistance. The pack supplies 100 pieces for repeated use across multiple joints or spare inventory.

How it compares

Measured against everything we stock in Bits, Hole Saws & Accessory Kits, at today’s prices. Recalculated every night.

Price $26.99
Typical for this category: the median of 5,493 items is $27.99.

Specifications

Product
Brand nameKerr Lakeside
Product typeSocket
Size & build
Main materialHAWA

Questions about this item

How do I install the 5/16-18 x 2.25 in socket head cap screw, and what step is often missed?

Use a 1/4 in hex key to drive the socket head; the step people miss is checking that the 1 3/8 in thread length engages fully before the unthreaded shank bottoms out.

What maintenance or replacement will these alloy steel screws with black oxide finish need later?

Inspect the black oxide coating for wear or corrosion; replace any screw showing stripped hex drive, stretched threads, or rust on the 5/16 in diameter shank.

What limit appears first when these partially threaded screws are under sustained clamping load?

The 1 3/8 in minimum thread length means the threaded zone yields or strips before the unthreaded shank reaches its shear capacity.

More in Bits, Hole Saws & Accessory Kits

Similar items