Steel Flat Head Half Hexagon Body Open End Rivet Nuts - M8 x 18mm | Shop4Fasteners
National Hardware N280-859 V7652 Flat Head Carriage Bolts and Nuts in Zinc plated, 12 pack,1/4" - 20 x 1-3/4" : NATIONAL HARDWARE: Amazon.co.uk: DIY & Tools
M8 8mm Flat Head Aluminum Rivet Nut Blind Insert Nut Pack of 100 : Amazon.co.uk: DIY & Tools
Flat Head Knock-In Insert Nut (IN16) | Fastenright Ltd