A4 Stainless Steel Left-Hand Thread Hex Bolts are supplied to DIN 933. The grade provides superior, including marine and chloride environments and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C, subject to the property class and the joint. Property data, grade comparison and the full size table follow.
Why Choose A4 Stainless Steel for Left-Hand Thread Hex Bolts
Specified for marine, coastal and chemical applications. For left-hand thread hex bolts, this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Superior, including marine and chloride environments |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For Left-Hand Thread Hex Bolts in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Galvanic & Galling Considerations
Two important notes for stainless left-hand thread hex bolts: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Using Stainless Fasteners in Aluminum
Expect the aluminum to corrode, not the fastener — stainless sits higher in the galvanic series, so the aluminum is the one that gives up material. A small fastener in a thick section spreads the loss over a large area and is usually fine; a large fastener in thin sheet concentrates it and is not. Keep water out of the joint, or isolate the two metals with a nylon or coated washer and a sealant.
Sizes of Left-Hand Thread Hex Bolts Available in A4 Stainless Steel
| Thread size | Pitch (mm) | Across flats s (mm) | Across corners e (mm) | Head height k (mm) | Thread direction | Common length range (mm) | Reference standard |
|---|---|---|---|---|---|---|---|
| M6 | 1.0 | 10 | 11.05 | 4.0 | Left-hand | 10~60 | DIN 933 LH |
| M8 | 1.25 | 13 | 14.38 | 5.3 | Left-hand | 12~80 | DIN 933 LH |
| M10 | 1.5 | 17 | 18.90 | 6.4 | Left-hand | 16~100 | DIN 933 LH |
| M12 | 1.75 | 19 | 21.10 | 7.5 | Left-hand | 20~120 | DIN 933 LH |
| M16 | 2.0 | 24 | 26.75 | 10.0 | Left-hand | 25~150 | DIN 933 LH |
| M20 | 2.5 | 30 | 33.53 | 12.5 | Left-hand | 30~150 | DIN 933 LH |
| M24 | 3.0 | 36 | 39.98 | 15.0 | Left-hand | 40~150 | DIN 933 LH |
Dimensions are independent of the material: every size above is available in A4 Stainless Steel.
Custom manufacturing · Made to drawing
Need this bolt in a grade that is not listed?
A4 Stainless Steel is one of the grades the catalog describes. Where the standard stops, the drawing takes over: fine pitches, left-hand threads, partial threading, and property classes above the catalogued grade where material and heat treatment allow. Made by cold heading or hot forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
