Nut: M8
Bolts:
M8x16
M8x20
M8x25
M8x30
M8x35
M8x50
Link to other Sizes:
M4: https://makerworld.com/en/models/243605#profileId-259987
M5: https://makerworld.com/en/models/243619#profileId-260002
M6: https://makerworld.com/en/models/243624#profileId-260008