Amazon.com: The Hillman Group 44966 M4 X 40 Metric Cotter Pin, 20-Pack : Industrial & Scientific
Bolt Base (4mm) M4 x 40 Stainless Steel Slotted Spring Tension Pins Sellock Roll Pins DIN 1481 - 5 Pack: Amazon.com: Industrial & Scientific
460 Pcs Roll Pin Assortment Set, Slotted Metric Spring Pins, Split Expansion Pins, Spring Dowel Tension Roll Pins, Split Expansion Spring Steel Pins Set - M1.5/M2/M2.5/M3/M4/M5/M6: Amazon.com: Industrial & Scientific