Pro Grip Studs 
Self clearing studs. The studs are machined to push the dirt out of the stud hole as you screw the stud in.
The PGS has a tungsten pin and a 9mm,13mm, 17mm or 21mm protrusion.
Ideal for SOFT ground.
Highest quality horseshoe studs are used by some of the leading riders in New Zealand and internationally.
For 3/8" stud holes.
Sold in a pack of 4 studs