Shop › RUGGED PISTON .578X28 RUGGED PISTON .578X28 $80.00 Rugged Suppressors Piston, 17-4 Stainless Steel, .578X28 Thread Pattern, Obsidian 45 OP001 Quantity: Add To Cart Added! Rugged Suppressors Piston, 17-4 Stainless Steel, .578X28 Thread Pattern, Obsidian 45 OP001