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// TECHNICAL RESOURCES

MS90728 Grade 8 coarse-thread hex cap screws.

Find MS90728 threads, under-head lengths, hex head dimensions and finish details. Filter the reference table and request a quote for a selected screw.

// DIMENSIONS & PART IDENTIFICATION

Hex cap screw length and head dimensions

Hex cap screw length and head dimensions
L is measured beneath the head to the tip. F is head width across flats, and H is axial head height. The partial threading is schematic; thread length and runout follow the governing specification.

Schematic only; not to scale. Letter labels are keys for this illustration. Use the applicable part specification for dimensions, tolerances and measurement conventions.

// PART IDENTIFICATION

Identify the grade, thread and finish

MS90728 identifies alloy-steel Grade 8 hexagon-head cap screws with UNC-2A threads. The reviewed issue specifies zinc coated parts. The table covers 97 selected references across 1/4, 5/16, 3/8, 1/2, 5/8 and 3/4-inch diameters, with listed under-head lengths through 3.000 inches. The 7/16 and 9/16-inch columns marked inactive for new design in the reviewed drawing are omitted. The reviewed issue states that this standard is not intended for aerospace applications.

// REFERENCE SIZES

MS90728 part-number and dimension table

Reference sizes for identification and quotation. Webson confirms availability by inquiry; these rows do not indicate stocked inventory.

MS90728 reference hex cap screw dimensions
Part numberThreadLength per drawing (in)Head across flats limits (in)Head height limits (in)Request pricing
MS90728-11/4-200.3750.4280–0.43750.150–0.163Quote MS90728-1 →
MS90728-21/4-200.4380.4280–0.43750.150–0.163Quote MS90728-2 →
MS90728-31/4-200.5000.4280–0.43750.150–0.163Quote MS90728-3 →
MS90728-41/4-200.5620.4280–0.43750.150–0.163Quote MS90728-4 →
MS90728-51/4-200.6250.4280–0.43750.150–0.163Quote MS90728-5 →
MS90728-61/4-200.7500.4280–0.43750.150–0.163Quote MS90728-6 →
MS90728-71/4-200.8750.4280–0.43750.150–0.163Quote MS90728-7 →
MS90728-81/4-201.0000.4280–0.43750.150–0.163Quote MS90728-8 →
MS90728-91/4-201.1250.4280–0.43750.150–0.163Quote MS90728-9 →
MS90728-101/4-201.2500.4280–0.43750.150–0.163Quote MS90728-10 →
MS90728-111/4-201.3750.4280–0.43750.150–0.163Quote MS90728-11 →
MS90728-121/4-201.5000.4280–0.43750.150–0.163Quote MS90728-12 →
MS90728-131/4-201.7500.4280–0.43750.150–0.163Quote MS90728-13 →
MS90728-141/4-202.0000.4280–0.43750.150–0.163Quote MS90728-14 →
MS90728-151/4-202.2500.4280–0.43750.150–0.163Quote MS90728-15 →
MS90728-161/4-202.5000.4280–0.43750.150–0.163Quote MS90728-16 →
MS90728-171/4-202.7500.4280–0.43750.150–0.163Quote MS90728-17 →
MS90728-181/4-203.0000.4280–0.43750.150–0.163Quote MS90728-18 →
MS90728-275/16-180.3750.4890–0.50000.195–0.211Quote MS90728-27 →
MS90728-285/16-180.4380.4890–0.50000.195–0.211Quote MS90728-28 →
MS90728-295/16-180.5000.4890–0.50000.195–0.211Quote MS90728-29 →
MS90728-305/16-180.5620.4890–0.50000.195–0.211Quote MS90728-30 →
MS90728-315/16-180.6250.4890–0.50000.195–0.211Quote MS90728-31 →
MS90728-325/16-180.7500.4890–0.50000.195–0.211Quote MS90728-32 →
MS90728-335/16-180.8750.4890–0.50000.195–0.211Quote MS90728-33 →
MS90728-345/16-181.0000.4890–0.50000.195–0.211Quote MS90728-34 →
MS90728-355/16-181.1250.4890–0.50000.195–0.211Quote MS90728-35 →
MS90728-365/16-181.2500.4890–0.50000.195–0.211Quote MS90728-36 →
MS90728-375/16-181.3750.4890–0.50000.195–0.211Quote MS90728-37 →
MS90728-385/16-181.5000.4890–0.50000.195–0.211Quote MS90728-38 →
MS90728-395/16-181.7500.4890–0.50000.195–0.211Quote MS90728-39 →
MS90728-405/16-182.0000.4890–0.50000.195–0.211Quote MS90728-40 →
MS90728-415/16-182.2500.4890–0.50000.195–0.211Quote MS90728-41 →
MS90728-425/16-182.5000.4890–0.50000.195–0.211Quote MS90728-42 →
MS90728-435/16-182.7500.4890–0.50000.195–0.211Quote MS90728-43 →
MS90728-445/16-183.0000.4890–0.50000.195–0.211Quote MS90728-44 →
MS90728-533/8-160.3750.5510–0.56250.226–0.243Quote MS90728-53 →
MS90728-543/8-160.4380.5510–0.56250.226–0.243Quote MS90728-54 →
MS90728-553/8-160.5000.5510–0.56250.226–0.243Quote MS90728-55 →
MS90728-563/8-160.5620.5510–0.56250.226–0.243Quote MS90728-56 →
MS90728-573/8-160.6250.5510–0.56250.226–0.243Quote MS90728-57 →
MS90728-583/8-160.7500.5510–0.56250.226–0.243Quote MS90728-58 →
MS90728-593/8-160.8750.5510–0.56250.226–0.243Quote MS90728-59 →
MS90728-603/8-161.0000.5510–0.56250.226–0.243Quote MS90728-60 →
MS90728-613/8-161.1250.5510–0.56250.226–0.243Quote MS90728-61 →
MS90728-623/8-161.2500.5510–0.56250.226–0.243Quote MS90728-62 →
MS90728-633/8-161.3750.5510–0.56250.226–0.243Quote MS90728-63 →
MS90728-643/8-161.5000.5510–0.56250.226–0.243Quote MS90728-64 →
MS90728-653/8-161.7500.5510–0.56250.226–0.243Quote MS90728-65 →
MS90728-663/8-162.0000.5510–0.56250.226–0.243Quote MS90728-66 →
MS90728-673/8-162.2500.5510–0.56250.226–0.243Quote MS90728-67 →
MS90728-683/8-162.5000.5510–0.56250.226–0.243Quote MS90728-68 →
MS90728-693/8-162.7500.5510–0.56250.226–0.243Quote MS90728-69 →
MS90728-703/8-163.0000.5510–0.56250.226–0.243Quote MS90728-70 →
MS90728-1041/2-130.5000.7360–0.75000.302–0.323Quote MS90728-104 →
MS90728-1051/2-130.5620.7360–0.75000.302–0.323Quote MS90728-105 →
MS90728-1061/2-130.6250.7360–0.75000.302–0.323Quote MS90728-106 →
MS90728-1071/2-130.7500.7360–0.75000.302–0.323Quote MS90728-107 →
MS90728-1081/2-130.8750.7360–0.75000.302–0.323Quote MS90728-108 →
MS90728-1091/2-131.0000.7360–0.75000.302–0.323Quote MS90728-109 →
MS90728-1101/2-131.1250.7360–0.75000.302–0.323Quote MS90728-110 →
MS90728-1111/2-131.2500.7360–0.75000.302–0.323Quote MS90728-111 →
MS90728-1121/2-131.3750.7360–0.75000.302–0.323Quote MS90728-112 →
MS90728-1131/2-131.5000.7360–0.75000.302–0.323Quote MS90728-113 →
MS90728-1141/2-131.7500.7360–0.75000.302–0.323Quote MS90728-114 →
MS90728-1151/2-132.0000.7360–0.75000.302–0.323Quote MS90728-115 →
MS90728-1161/2-132.2500.7360–0.75000.302–0.323Quote MS90728-116 →
MS90728-1171/2-132.5000.7360–0.75000.302–0.323Quote MS90728-117 →
MS90728-1181/2-132.7500.7360–0.75000.302–0.323Quote MS90728-118 →
MS90728-1191/2-133.0000.7360–0.75000.302–0.323Quote MS90728-119 →
MS90728-1555/8-110.6250.9220–0.93750.378–0.405Quote MS90728-155 →
MS90728-1565/8-110.7500.9220–0.93750.378–0.405Quote MS90728-156 →
MS90728-1575/8-110.8750.9220–0.93750.378–0.405Quote MS90728-157 →
MS90728-1585/8-111.0000.9220–0.93750.378–0.405Quote MS90728-158 →
MS90728-1595/8-111.1250.9220–0.93750.378–0.405Quote MS90728-159 →
MS90728-1605/8-111.2500.9220–0.93750.378–0.405Quote MS90728-160 →
MS90728-1615/8-111.3750.9220–0.93750.378–0.405Quote MS90728-161 →
MS90728-1625/8-111.5000.9220–0.93750.378–0.405Quote MS90728-162 →
MS90728-1635/8-111.7500.9220–0.93750.378–0.405Quote MS90728-163 →
MS90728-1645/8-112.0000.9220–0.93750.378–0.405Quote MS90728-164 →
MS90728-1655/8-112.2500.9220–0.93750.378–0.405Quote MS90728-165 →
MS90728-1665/8-112.5000.9220–0.93750.378–0.405Quote MS90728-166 →
MS90728-1675/8-112.7500.9220–0.93750.378–0.405Quote MS90728-167 →
MS90728-1685/8-113.0000.9220–0.93750.378–0.405Quote MS90728-168 →
MS90728-1793/4-100.7501.1000–1.12500.455–0.483Quote MS90728-179 →
MS90728-1803/4-100.8751.1000–1.12500.455–0.483Quote MS90728-180 →
MS90728-1813/4-101.0001.1000–1.12500.455–0.483Quote MS90728-181 →
MS90728-1823/4-101.1251.1000–1.12500.455–0.483Quote MS90728-182 →
MS90728-1833/4-101.2501.1000–1.12500.455–0.483Quote MS90728-183 →
MS90728-1843/4-101.3751.1000–1.12500.455–0.483Quote MS90728-184 →
MS90728-1853/4-101.5001.1000–1.12500.455–0.483Quote MS90728-185 →
MS90728-1863/4-101.7501.1000–1.12500.455–0.483Quote MS90728-186 →
MS90728-1873/4-102.0001.1000–1.12500.455–0.483Quote MS90728-187 →
MS90728-1883/4-102.2501.1000–1.12500.455–0.483Quote MS90728-188 →
MS90728-1893/4-102.5001.1000–1.12500.455–0.483Quote MS90728-189 →
MS90728-1903/4-102.7501.1000–1.12500.455–0.483Quote MS90728-190 →
MS90728-1913/4-103.0001.1000–1.12500.455–0.483Quote MS90728-191 →

Head across-flats width and axial head height are minimum–maximum drawing limits in inches. Length values preserve the reviewed table’s decimal references, including 0.438 and 0.562; they do not add acceptance tolerances. Across-flats limits describe the screw head, not the tolerance of a wrench or socket.

// MEASUREMENT GUIDE

Measure under-head length and head dimensions

Length L runs from the bearing surface beneath the head to the tip. H is the axial head height; F is the width between opposite hex faces. The head is outside the under-head length measurement.

Thread length is a separate requirement. The reviewed issue uses a minimum rule of twice the nominal diameter plus 1/4 inch, with a positive allowance and separate provisions for screws too short to provide that thread length. Use the full governing issue for those limits. A listed screw length is not a fixed grip length or a claim that the screw is fully threaded.

// ORDERING EXAMPLES

Read the complete part number

MS90728-3 is a 1/4-20 reference with a 0.500-inch under-head length. MS90728-109 is a 1/2-13 reference with a 1.000-inch under-head length. Use the full series and dash number when ordering.

// MATERIAL AND CONFIGURATION

Preserve the finish and locking requirement

The reviewed MS90728G reference specifies alloy steel, Grade 8, with zinc coating. Earlier issues used cadmium plating; retain the coating and specification issue called out by your drawing.

The table lists plain screws. The reviewed part-number requirements use an L after the dash number for a self-locking element. Preserve that suffix and the locking requirement when applicable; a plain screw and a locking configuration are separate selections.

// FAMILY COMPARISON

Compare the four hex cap screw families

Grade 5 and Grade 8 hex cap screw comparison
SeriesSteel gradeThread seriesFinish in reviewed issue
MS90725Grade 5UNC-2ACadmium plated
MS90726Grade 5UNF-2ACadmium plated
MS90727Grade 8UNF-2AZinc coated
MS90728Grade 8UNC-2AZinc coated

Compare grade, thread, finish and governing issue together. A similar head size does not establish an approved substitution. Select mating nuts and washers to the application’s strength, finish and dimensional requirements.

// DRAWING REQUIREMENTS

Match the governing drawing issue

Dimensions summarize MS90728G, pages 1–3, 4 November 1988. These are selected historical references for purchasing identification. The issue required by your drawing controls full dimensions, thread length, material, coating, locking and inspection requirements.

// BUYER CHECKLIST

Prepare the requirement for quotation

// SOURCE WITH WEBSON

Have a part number or bill of material?

Send the complete designation, quantity, required delivery date and documentation requirements. Webson will review your requirement for quotation.