18-8 Stainless Steel Pan Head Screws with Spring Lock Washer
4-40 Thread Size, 1/4" Long
Locking Type | Lock Washer |
Thread | |
Size | 4-40 |
Direction | Right Hand |
Spacing | Coarse |
Type | UNC |
Fit | Unified Standard Class 2A |
Tip Type | Flat |
Fastener Head Type | Rounded |
Head | |
Style | Pan |
Profile | Standard |
Height | 0.08" |
Diameter | 0.219" |
Drive | |
Style | Phillips |
Size | No. 1 |
Washer | |
Type | Domed |
Material | 410 Stainless Steel |
OD | 0.25" |
Thickness | 0.015" |
Lock Washer Type | Spring |
Length | 1/4" |
Threading | Fully Threaded |
Tensile Strength | 70,000 psi |
Specifications Met | ASME B18.13 |
Certificate Form | Digital |
Certificate Type | Material Certificate with Traceable Lot Number |
Hardness | Rockwell B80 |
Material | 18-8 Stainless Steel |
Passivation | Passivated |
Performance | Corrosion Resistant, Vibration Resistant |
Screw Size Decimal Equivalent | 0.112" |
System of Measurement | Inch |
Country of Origin | Taiwan |
DFARS Compliance | Not Specialty Metals Compliant |
Export Control Classification Number (ECCN) | EAR99 |
REACH Compliance | REACH (EC 1907/2006) (06/25/2025, 250 SVHC) Compliant |
RoHS Compliance | RoHS 3 (2015/863/EU) Compliant |
Schedule B Number | 731815.9000 |
U.S.–Mexico–Canada Agreement (USMCA) Qualifying | No |
These corrosion-resistant screws grip tighter for better vibration resistance than screws with tooth-lock washers. The spring-like washer flexes to keep tension constant and to compensate for uneven surfaces, vibration changes, and temperature shifts. They have a moderate height and width profile, offering a middle ground between narrower button heads and wider truss heads. The Phillips drive easily aligns with drivers and withstands more torque than slotted drives, but drivers slip when you apply too much force. Also known as Square Cone Sems screws.
Length is measured from under the head.
18-8 Stainless Steel—The choice for wet and outdoor environments, these screws won't rust. However, they don't hold up to the harsh chemicals that 316 stainless steel can.
The information in this 3-D model is provided for reference only.