Flange bolts

are those type of bolts having a ridge or skirt around the bolt head. They are also know as frame bolts and are designed to provide the holding power as if a washer was installed. Please check the types as below:
Hex Bolts
Hexagon Socket Bolts
Eye Bolts
Carriage Bolts
Hammer / Channel Bolts
T-Head Bolts
Oval Neck Track Bolts
OEM Special Bolts
 
Standard:
DIN 931, DIN 933, DIN 558, DIN 601, DIN 960, DIN 961, ISO 4014, ISO 4017, JIS B 1180, ANSI B 18.2.1
Mechanical Properties:
Metric Grades : 4.6, 8.8, 10.9, 12.9
Inch Grades : 2, 5, 8
Mechanical Properties:
Material: A193 B7/A194 2H; A193 B7M/A194 2HM; A193 B8/A194 8; A193 B8M/A194 8M; A193 B16/A194 4/7; A320 L7/A194 4/7; A320 L7M/A194 7M
Surface: black, galvanized, nickel plated, cadmium plated, Teflon plated