A helmet (A) with a chin strap (A2) to reliably secure it to a user's head. The chin strap (A2) is comprised of a retainer strap (1) having a fastening member (e.g.: 'D '-ring) (1a) and an operational band (2) intended to be tightly fastened through the fastening member (1a) of the retainer strap (1). The retainer strap (1) is provided at its free end, typically above the fastening member (1a), with either a male or female connector means (4a) (e.g.: "snap" ) , and the operational strap (2) is provided at its free end with the mating connector means (4b).
