Hex Bolts & Cap Screws

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Expected delivery: Wed, Nov 18

Hex bolts and hex cap screws are the workhorse fasteners for machinery, structural brackets, truck bodies and equipment repair. This section covers inch sizes in UNC and UNF threads and metric sizes in class 8.8 and 10.9, with partial or full threads. Materials include Grade 2, Grade 5 and Grade 8 steel plus 18-8 and 316 stainless, in plain, zinc, yellow zinc and hot-dip galvanized finishes.

What to check before you order

Grade or property class. Match the grade to the load. Grade 5 covers most equipment work, and Grade 8 is for high-stress joints such as suspension and heavy machinery. The hex bolt grades guide shows head markings.
Thread pitch. A 1/2" bolt comes in 1/2"-13 coarse and 1/2"-20 fine. They will not interchange, so confirm the nut or tapped hole first.
Length and thread length. Measure from under the head. Longer bolts are often partially threaded, which leaves a smooth shank in the shear plane.
Finish. Hot-dip galvanized bolts need galvanized nuts, because the coating adds thickness to the threads.

Common questions

Is a Grade 8 bolt always the safer choice?

Not always. Grade 8 is stronger but less ductile than Grade 5. Use the grade the equipment maker or engineer specifies.

Pair your bolts with matching nuts and washers, or browse all fasteners.

Hex Bolts & Cap Screws: page 18

Approved Vendor 3/8"-16x3-1/2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22577 $5.65
Approved Vendor 3/8"-16x3/4" Aluminum Hex Head Cap Screw SKU 22583 $3.35
Approved Vendor 3/8"-16x3/4" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22587 $1.66
Approved Vendor 3/8"-16x4" Aluminum Hex Head Cap Screw SKU 22595 $10.56
Approved Vendor 3/8"-16x4" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22596 $6.33
Approved Vendor 3/8"-16x4-1/2" Aluminum Hex Head Cap Screw SKU 22599 $12.14
Approved Vendor 3/8"-16x4-1/2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22600 $8.34
Approved Vendor 3/8"-16x5" Aluminum Hex Head Cap Screw SKU 22603 $8.80
Approved Vendor 3/8"-16x5" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22604 $9.07
Approved Vendor 3/8"-16x5-1/2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22607 $9.77
Approved Vendor 3/8"-16x6" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22616 $10.48
Approved Vendor 3/8"-24 Fine 18-8 Stainless Steel Hex Cap Screws, Nuts, & Washers - 378 PCS SKU 22643 $160.47/pack of 378
Approved Vendor 3/8"-24 Fine 18-8 Stainless Steel Hex Cap Screws, Nuts, & Washers - 754 PCS SKU 22644 $194.69/pack of 754
Approved Vendor 3/8"-24 Fine 18-8 Stainless Steel Hex Cap Screws, Nuts, & Washers - 755 PCS SKU 22645 $253.83/pack of 755
Approved Vendor 3/8"-24 Fine Grade 5 Hex Cap Screws, Nuts, & Washers - 378 PCS SKU 22646 $110.08/pack of 378
Approved Vendor 3/8"-24 Fine Grade 5 Hex Cap Screws, Nuts, & Washers - 754 PCS SKU 22647 $112.23/pack of 754
Approved Vendor 3/8"-24 Fine Grade 5 Hex Cap Screws, Nuts, & Washers - 755 PCS SKU 22648 $171.38/pack of 755
Approved Vendor 3/8"-24 Fine Grade 8 Hex Cap Screws, Nuts, & Washers - 378 PCS SKU 22649 $129.51/pack of 378
Approved Vendor 3/8"-24 Fine Grade 8 Hex Cap Screws, Nuts, & Washers - 754 PCS SKU 22650 $144.02/pack of 754
Approved Vendor 3/8"-24 Fine Grade 8 Hex Cap Screws, Nuts, & Washers - 755 PCS SKU 22651 $203.17/pack of 755
Approved Vendor 3/8"-24x1" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22712 $2.24
Approved Vendor 3/8"-24x1-1/2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22713 $2.96
Approved Vendor 3/8"-24x1-1/4" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22714 $2.57
Approved Vendor 3/8"-24x1-3/4" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22715 $3.38
Approved Vendor 3/8"-24x2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22720 $3.78
Approved Vendor 3/8"-24x2-1/2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22721 $4.55
Approved Vendor 3/8"-24x3" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22723 $5.39
Approved Vendor 3/8"-24x3-1/2" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22724 $6.37
Approved Vendor 3/8"-24x3/4" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22727 $1.92
Approved Vendor 3/8"-24x4" Hex Cap Screws Grade L-9 Bolts USA Zinc Yellow SKU 22730 $7.15
Approved Vendor 3/8-16x1" Grade 5 Serrated Hex Flange Bolts Zinc Yellow SKU 22846 $0.79
Approved Vendor 3/8-16x1" 18-8 Stainless Steel Serrated Hex Flange Bolts SKU 2096 $1.65
Approved Vendor 3/8-16x1" Brass Hex Tap Bolts Full Thread SKU 22861 $4.37
Approved Vendor 3/8-16x1" Grade 5 Hex Flange Bolts Zinc Clear SKU 22862 $0.85
Approved Vendor 3/8-16x1" Grade 5 Serrated Hex Flange Bolts Zinc Clear SKU 22864 $0.83
Approved Vendor 3/8-16x1" Grade 5 Serrated Hex Large Flange Bolts Zinc Clear SKU 22865 $1.06
Approved Vendor 3/8-16x1" Grade 8 Hex Flange Frame Bolts Phos & Oil SKU 22866 $1.13
Approved Vendor 3/8-16x1" Grade 8 Hex Flange Frame Bolts Zinc Yellow SKU 22867 $1.39
Approved Vendor 3/8-16x1" Grade 8 Serrated Hex Flange Bolts Zinc Clear SKU 22869 $0.97
Approved Vendor 3/8-16x1" Hex Cap Screws Grade 5 Bolts Zinc Clear SKU 22870 $0.41
Approved Vendor 3/8-16x1" Hex Head Cap Screws Grade 8 USA Zinc Yellow SKU 22871 $0.75
Approved Vendor 3/8-16x1" Hex Head Cap Screws Grade 8 Zinc Yellow SKU 22872 $0.59
Approved Vendor 3/8-16x1" Stainless Steel Hex Cap Screws Bolts SKU 1158 $0.77
Approved Vendor 3/8-16x1-1/2" 18-8 Stainless Steel Serrated Hex Flange Bolts SKU 2098 $2.04
Approved Vendor 3/8-16x1-1/2" Brass Hex Tap Bolts Full Thread SKU 22891 $5.84
Approved Vendor 3/8-16x1-1/2" Grade 5 Hex Flange Bolts Zinc Clear SKU 22895 $1.09
Approved Vendor 3/8-16x1-1/2" Grade 5 Serrated Hex Flange Bolts Zinc Clear SKU 22897 $1.07
Approved Vendor 3/8-16x1-1/2" Grade 5 Serrated Hex Flange Bolts Zinc Yellow SKU 22898 $0.94

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