New Bowmalloy FKE 200+, High Strength Alloy, Socket Head Cap Screws / Allen Head Bolts, 1"-8 x 2-1/2," Catalog Number 490186.  Each bid quantity is for a Box of Ten (10) Bolts.  You may bid / buy any number of boxes, up to the total quantity available above.

This batch of bolts was purchased at an industrial liquidation last year, and they are brand new in the original factory boxes.  These were distributed by Barnes Distribution, which declares them to be the strongest standard socket head bolts on the market (press release below).  They are manufactured from a proprietary alloy which yields extremely high tensile strength.  They also have a special radius beneath the head that is designed to provide resistance to shear-off and fatigue at the first thread, which is the place where most bolts tend to fail.

According to the calipers

Overall length:  3.495"

Length (head to tip):  2.500"

Head diameter:  1.495"

Head height:  .990"

Drive bit size:  3/4" Hex

Threads:  1-8 x 2-1/2" (diameter - threads per inch x length)

Head marking:  FKE 200+

Box label:

FKE 200+
Socket Head Cap Screw
1-8 x 2-1/2
490186   Qty. 10
Lot No. (varies)
Made in Taiwan
Barnes Distribution
Barnes Group, Inc

According to the manufacturer:

The new fasteners, the FKE 200+, are part of the Bowmalloy Plus product line, and expand and enhance our comprehensive line of Bowmalloy fasteners.

The Bowmalloy Plus line of high-strength socket head cap screws are designed for machine tools, tools and dies, earth moving and mining machinery, and a wide range of industrial and engineering applications. Independent lab tests show that Bowmalloy Plus Socket Head Screws are stronger than any standard socket head cap screw on the market.

Bowmalloy Plus Socket Head Screws easily replace standard socket head cap screws as they have the same dimensional characteristics as standard socket head cap screws. Produced from a proprietary material, these socket screws have higher tensile/yield strength and proof loads than any brand of socket. A patented fillet radius reduces fatigue failures at the head of the screw, one of the leading causes of socket screw failure. In addition, unique thread design and sandblasting after manufacturing all add to the strength and durability of the product.