Type

Hex Bolt

Designation

ST8 × 3.4 – 200

Head

Pan · Ø15 × 3 mm

Drive

Torx · 6 mm key

Recess depth

1.5 mm · auto · gauge limits t 1.2–1.8 mm · ISO 10664

Thread

80.00/200 mm · P3.4 · ST sheet-metal (ISO 1478) · plain shoulder 120.0 mm

Major Ø (as built)

7.80 mm

Point

Self-Tapping Gimlet · 12.80 mm

Timber thread

High-Low Asymmetric + milling section · 4-slot cut point

Milling section

20 mm × 8 ribs — reams the pilot hole, lower drive torque

Material / coating

C10B21 Boron Steel · Zinc Yellow · 120 h salt spray

Trade size

#20 × 7-7/8"

Service class

C3 · Outdoor urban · coating under-rated — use dip-spin ceramic coating

Est. install torque

≈ 11.2 N·m (indicative — verify by test)

Est. pull-out

≈ 7.7 kN from C24 timber (indicative)

Manufacturing mode

FDM 3D print · +0.2 mm thread offset

Notes

T40 drive. ETA/CE structural application.