The Ultimate spring range was developed by Eric Grauffel and his team to improve your shooting sensation. These springs are ideal for shooting in competition, they will guarantee lightness and performance. This spring is compatible with all the CZ 75 type of pistols. (CZ75, CZ97, CZ P-09, CZ SHADOW 2, CZ75 SP-01, CZ75 TS including Czechmate and TS 2.) Whether in Double Action or Single Action, the Hammer Spring Ultimate optimizes starting weights according to the needs and ammunition used. The tests are carried out on a Shadow 2 factory weapon. On 10 weighings, the highest and the lowest are removed. The average is carried out on the eight remaining weighings.