Lot of 20 SVSQS-M3-6 NBK Cross Recessed Flat Head M3 length 6mm Vacuum Vented Screws Made in JapanLot of 20 SVSQS M3 6 NBK Cross Recessed Flat Head M3 length 6mm Screws SVSQS M3 6 NBK Hex Socket Head Cap Screws with Captive Washer and Ventilation Hole. Pack of 20 NBK Hex Socket Head Cap Screws with Captive Washer and Ventilation Hole. Part Number M L D1 D L1 B t T (Approx.) d (max.) SVSQS M3 5 3mm 6mm 5. 5mm 7mm 3mm 2. 5mm 0. 5mm 0. 7 1. 2 The ventilation hole easily releases gas trapped in the screw holes of equipment and machines, and supports