Used two different sizes
1/4-20 for center with breakaway security nuts
1/4-20 x 1-1/2" Carriage Bolts, Round Head, Square Neck, Stainless Steel 18-8, Full Thread, Plain Finish, Flat Point, Quantity 50 by Fastenere https://a.co/d/f5s2Lj9
SNUG Fasteners (SNG323) Ten (10) 3/8-16 x 3/4" Long...