Thirty-five ASTM, SAE, ASME, ISO, and DIN standards in plain English — and in the depth a specifying engineer actually needs. Bolts, nuts, washers, threads, coatings, and metric reference. Every page opens with an “at-a-glance” so non-specialists can get oriented in ten seconds.
Most engineers don't arrive here knowing the spec number. Pick the path that matches what's already on your desk — a drawing, an application, or an environment.
Carbon, alloy, stainless, and specialty bolts — from general-purpose A307 through heavy-duty A540 turbine bolting. Ordered by how often we ship them.
Consolidates A325, A490, F1852, F2280. If you read a structural drawing this decade, you're reading F3125.
The workhorse of pressure flanges, ASME B16.5 connections, and valve bonnets.
Straight, bent, or headed. The AISC-referenced spec for cast-in-place anchors.
Charpy-tested down to −150°F. L7M is NACE MR0175 for sour service.
Group 1 = 304-class, Group 2 = 316-class, Group 3 = duplex & precipitation-hardening.
Grade A for general mechanical. Grade B for pressure flanges below 500°F.
Used when you need more than A449 but structural F3125 isn't a fit.
Think SAE Grade 5, but available above 1-1/2″ diameter. Type 3 is weathering steel.
Jet engines, gas turbines. A286 at 1200°F+ where B7 and B16 fall off.
Specifically for steam turbines. Heat-treat ranges chosen for creep resistance.
The highest strength in common inch-series fasteners. Allen-drive.
The grade you pick up at any hardware store. Grade 5 and 8 are the auto-industry standards.
Structural, pressure, stainless, and nonferrous nuts. Every bolt grade in this library has a matching nut grade in this section.
The definitive match for A193 studs. 2H pairs with B7; 7M with L7M; 8M with B8M.
DH is the heavy-hex structural nut. DH3 is atmospheric-corrosion-resistant (weathering).
The F593 counterpart. Groups align with the bolt spec for matched galvanic behavior.
When galvanic compatibility matters more than strength. Silicon bronze for marine hardware.
Matched proof-load ratings for SAE J429 bolts.
Hardened, plain, and direct-tension-indicating washers. F844 where F436 is required is the most common field error — we'll tell you how to avoid it.
Required under every A325/A490 bolt head and nut. Type 3 is weathering-steel compatible.
General-purpose only. Never substitute where F436 is specified — common field error.
Protrusions that crush at target tension. The inspector's friend; the installer's headache.
Inch, metric, pipe, and fit class. Every thread callout decoded — from 1/2-13 UNC-2A to M10×1.5-6g.
UNC is coarse. UNF is fine. UNJ has a controlled root radius — high-fatigue applications.
The M series. Pitch is called out in millimeters (e.g. M10×1.5).
Tapered. Seals on the threads. NPTF is dryseal — no sealant needed.
2A/2B is the default for 95% of inch fasteners. 3A/3B for aerospace and tight tolerances.
Zinc, fluoropolymer, cadmium. How each works, what it's approved for, and what it will and won't protect against.
Zinc-iron alloy. Most durable outdoor coating for carbon steel. Supersedes A153 Class C.
Thin, bright, cheap. Indoor and mild outdoor use only.
Only zinc coating process approved for A490 high-strength bolts. No hydrogen embrittlement risk.
The modern cadmium replacement. Thin, friction-controlled, salt-spray resistant.
Color-coded PTFE-based coatings. Controlled torque, deep-sea corrosion resistance.
Restricted under REACH/RoHS. Included for legacy drawings; see Zinc-Flake for replacements.
ISO property classes and their inch-spec equivalents. The bridge between drawings in M and parts on the shelf in inches.
Class 8.8 ≈ SAE Grade 5. Class 10.9 ≈ Grade 8. Class 12.9 has no common inch equivalent.
The source document behind every M-class callout. F568M is the US adaptation.
A2 ≈ 304. A4 ≈ 316. The metric counterpart to F593.
Dimensions only — pair with ISO 898-1 or ISO 3506 for the material properties.
The metric equivalent of ANSI B18.2.2 hex nuts. Pair with 8.8 or 10.9 bolts.
PDF, drawing, BOM, or a sketch on a napkin — we'll quote it. Most of the specs in this library are part of what we stock or source on short lead times, with mill certificates traceable to heat number.