Common Fastener Abbreviations - MonsterBolts
A great source of common fastener abbreviations and their meaning. We have added website links for those that we could (ASME, ASTM, DIN, ISO, RoHS etc...). If there is something we missed, please let us know and we will be sure to add it to the list.
Abbreviation Meaning |
|
| &NT | With Nut |
| 18-8 | Stainless Steel with 18% Chrome and 8% Nickel. Most Common Stainless Steel used with fasteners. |
| 2, 5 or 8 | US Strength grade for Screws and Nuts |
| A2 | Most common fastener grade Stainless Steel (aka 18-8, 304) |
| A4 | Marine Grade Stainless Steel (aka 316) |
| AS | Alloy Steel |
| ASME | American Society of Mechanical Engineers |
| ASTM | American Society for Testing and Materials. |
| A194 | Specifications for Carbon, Alloy and Stainless Steel nuts |
| A307 | Relates to carbon, alloy and stainless steel nuts for bolts. |
| A325 | Relates to Heavy Hex Structural Bolt, similar to Grade 5. |
| A490 | Relates to alloy steel Heavy Hex Structural Bolt, similar to Grade 8 |
| A449 | Relates to Steel Hex Cap screws, bolts and studs |
| A563 | Specification for Carbon and Alloy steel nuts |
| A574 | Specifications for Alloy Steel Socket Head Cap screws |
| F436 | Specifications for US and Metric Hardened Steel Washers |
| F594 | Specifications for Stainless Steel Nuts |
| F835 | Specifications for Alloy Steel Button Head and Flat Countersunk Socket Cap screws |
| F836M | Specifications for Metric 'Style 1' stainless steel nuts |
| F837 | Specifications for Stainless Steel Socket Head Cap Screws |
| F912 | Specifications for Alloy Steel Socket Set Screws |
| BHCS | Button Head Cap Screw (button head screw that takes a hex key to drive) |
| BLK OX | Black Oxide, an exterior finish commonly used on steel fasteners that has a black appearance |
| BSF | British Standard Fine |
| CL. | Class (used for metric fasteners) |
| CR | Chrome |
| CSS | Counter Sunk Screw |
| CT | Coarse Thread |
| DIN | Metric - Deutsches Institut für Normung, the German standards system that generally uses a 3 or 4 digit number to simply classify fasteners. |
| DIN 84 | Slotted Cheese Head Machine Screw |
| DIN 85 | Slotted Pan Head Machine Screw |
| DIN 94 | Cotter Pin |
| DIN 125A | Flat Washer (without Chamfer) |
| DIN 125B | Flat Washer (with Chamfer) |
| DIN 127B | Split Lock Washer |
| DIN 137B | Spring Wave Washer |
| DIN 315 | Wing Nut |
| DIN 439B | Machine Screw Hex Nut, Finished Hex Jam Nut |
| DIN 911 | Long Arm Hex Key |
| DIN 912 | Hex Socket Head Cap Screw |
| DIN 916 | Hex Socket Set Screw |
| DIN 931 | Hex Head Cap Screw Partially Threaded |
| DIN 933 | Hex Head Cap Screw Fully Threaded |
| DIN 934 | Finished Hex Nut |
| DIN 939 | Double End Stud |
| DIN 960 | Hex Head Cap Screw Partially Threaded |
| DIN 961 | Hex Head Cap Screw Fully Threaded |
| DIN 963 | Slotted Flat Head Machine Screw |
| DIN 964 | Slotted Oval Head Machine Screw |
| DIN 965 | Phillips Flat Head Machine Screw |
| DIN 966 | Phillips Oval Head Machine Screw |
| DIN 975 | Threaded Rod |
| DIN 980V | Hex Steel Prevailing Torque Lock Nut |
| DIN 985 | Hex Nylon Insert Lock Nut |
| DIN 6334 | Rod Coupling Nut |
| DIN 6797A | External Tooth Lock Washer |
| DIN 6797J | Internal Tooth Lock Washer |
| DIN 6912 | Hex Low Socket Head Cap Screw |
| DIN 6921 | Hex Flange Head Screw |
| DIN 6923 | Hex Flange Nut |
| DIN 7985 | Phillips Pan Head Machine Screw |
| DIN 7991 | Hex Flat Socket Head Cap Screw |
| ISO 7379 | Hex Socket Head Shoulder Screw |
| ISO 7380 | Hex Button Socket Head Cap Screw |
| EPDM | Ethylene Propylene Diene Monomer. Rubber used on roofing washers to properly seal them. Often used with Self-Drilling screws. |
| FH | Flat Head (Countersunk screw) |
| FHCS | Flat Head Cap Screw (flat head screw that takes a hex key to drive) |
| FIL | Fillister Head |
| FIN | Finishing Washer |
| FNDR | Fender Washer (Washer with a much larger outside diameter than normal) |
| FT | Fine Thread or Fully Threaded |
| G | Grade (also, GR - used for US fasteners) |
| Galv. | Galvanized (also GV) |
| HD | Head |
| HHMB | Hex Head Machine Bolt |
| HVHX | Heavy Pattern Hex Bolt |
| HX | Hex |
| ID | Inside Diameter (commonly used with washers) |
| ISO | International Organization for Standardization - |
| JMNT | Jam Nut |
| LB | |
| LBS |
Weight in Pounds |
| LH | Left Hand Thread |
| LW | Lock Washer |
| M | Metric |
| MB | Machine Bolt (also MonsterBolts) |
| MS | Machine Screw |
| MSNT | Machine Screw Nut |
| NC | National Coarse Thread (also C) |
| NF | National Fine Thread |
| NT | Nut |
| OD | Outside Diameter |
| OH | Oval Head (also OV) |
| P | Phillips (also PH, Phil.) |
| PN | Pan Head |
| PT | Partial Thread |
| RD | Round Head (also RH) |
| RH | Round Head or Right-Hand Thread |
| RoHS | Restriction of Hazardous Substances |
| S | Slotted Drive |
| SAE | SAE Pattern (Washers) or to indicate US Fine Thread screws |
| SBR | Silicon Bronze |
| SD | Square Drive / Self Drilling |
| SDS | Self-Drilling Screw |
| SEMS | A type of pre-made screw and washer assembly |
| SES | Sealed Electrical System |
| SHCS | Socket Head Cap Screw |
| SKT | Socket |
| SL | Slotted (also Slot.) |
| SMS | Sheet Metal Screw |
| SQ | Square (Drive or Head type) |
| SS | Stainless Steel, Set Screw |
| SSS | Socket Set Screw (set screw that takes a hex key to drive) |
| Ti | Titanium |
| UNC | Unified Coarse Thread (US Coarse thread) |
| UNEF | Unified Extra-Fine Thread (US Extra Fine Thread, rarely used) |
| UNF | Unified Fine Thread (US Fine Thread) |
| USS | USS Pattern (washers) or to indicate US coarse Thread screws |
| WS | Wood Screw |
| Z | Zinc |
| Zn | Zinc |