DW Hardware DWSM375S True Pitch Tension Rods TP30True Pitch tension rods by DW give a drummer increased control over their sound through 30 threads per inch. The additional threads widen a shell's tuning range and empowers drummers to dial in tuning to their specific tastes. This 6 pack of stainless steel DW True Pitch tension rods are intended for kick drums. Features Thirty threads per inch (TP30) Stainless steel tension rods 4. 375" [111. 1mm]