Bi-Directional Hard-Hit Hammers are fluid activated. Once fluid has ran through the BHA simply pulling tension or compression will initiate the hammering affect. Without tension or compression it gives a vibration effect. At maximum performance the hammers are capable of producing up to 32,000lbs of force in both tension and compression. The Bi-Directional Hard-Hit Hammers are recommended to be ran with Renown’s Suppressor.