M4-0.7X18 ISO7045 Metric Phil Pan 410SS Internal Washer Sems MS Ful Thread A2 Stainless Steel (Pack Qty 1,500) BC-MI418IPPA2

The washer/screw assembly makes this a locking screw with the washer providing the locking action. Machine pre-assembly provides cost savings to the end user. The internal tooth variety is recommended when it is desirable to hide the teeth for appearance or to prevent snagging Screw - Internal Tooth Lockwasher- Class 4.8 Steel: C1008 or equivalent carbon steel. C1050 Carbon Steel. Screw - Internal Tooth Lockwasher- Stainless: A2 Stainless