A steel cord (10) adapted for the reinforcement of rubber products, the steel cord (10) comprises a core (12) and three or more outer strands (14) twisted around the core (12) in a cord twisting direction. The outer strands (14) comprise outer filaments (16) twisted in a strand twisting direction which is the same as the cord twisting direction. The outer strands (14) have a wavy form which makes spaces between the core (12) and the outer strands. The steel cord (10) has improvements on elongation at break and impact resistance capacity.