Stromsholm Tungsten Centre StudsTungsten steel centre. 3 8" thread. 4 types. Set of 4. Types: H For most equestrian activities, such as jumping & eventing, when there is good to soft ground. TS For most equestrian activities, such as jumping & eventing, when competing on a hard ground. L For most equestrian activities, such as jumping & eventing, when a shorter stud is required. EL Suitable for hacking, hunting, all road work and interchanging with jumping and polo studs.