... /4" is pressed in trailer wheel, yellow zinc plated. Standard trailer wheel bolt for US/Canada market TRALER WHEEL BOLT/ STUDMaterial : high ... yellow zinc plating )Stud Grade : US standard Grade 8 wheel bolt key dimensions: overall length 2 1/4 ", thread ... 5x 5.0"BC trailer wheel hubUse for land-trailer hub , marine trailer hub , boat trailer hub wheel bolt (stud) pressed in trailer hub and drum