Fittment: 

GM C & K Trucks 1999-On
For GM Part Numer 15733970, 15733971
 
Size:
 Small Head Diameter: 18mm (0.71")
 Medium Head Diameter: 26mm (1.02")
 Flange Diameter: 30mm (1.18")
 Stem Length: 24mm (0.95")
40x   Clips  an  order