How to Measure an Oval-Head Screw
Oval heads require care because the crown projects above the seating surface.

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crown (not in length)
rim of countersink
QUICK RULE
Oval heads require care because the crown projects
above the seating surface.
LENGTH
TOP VIEW
Identify the exact product standard before using an overall-length convention.
Measure diameter and thread first.
For replacement work, compare the countersunk bearing portion and the projecting oval crown
separately.
Do not assume an oval-head screw is measured exactly like a flat head solely because both
use a countersink.
Use the governing ASME/product drawing for the nominal-length datum.
IDENTIFICATION ORDER
Product -> diameter -> thread -> length -> head/drive -> grade/material -> finish -> governing specification
REFERENCE ONLY. Verify the current ASME/SAE/ASTM/ISO/OEM standard and manufacturer data. Do not use as the sole basis for critical fastener selection or installation.
Fastener Guide reference FG-2FA903 · thefastenerapp.com/fastener-guide/measure-and-identify/how-to-measure-an-oval-head-screw · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.

























