Abstract: A protective helmet is composed of an external crown made from plastic material, and a semi-rigid neckband adjustable by adjustment means. At least one end of the neckband is joined to the crown by a sliding mechanical link comprising position indexing means controlled from a slide able to be moved from the outside in a slit of the crown. The indexing means are formed by a rack molded directly along with the crown.

Abstract: A protective helmet is composed of an external crown made from plastic material, and a semi-rigid neckband adjustable by adjustment means. To ensure that the helmet is efficiently secured on the user's head regardless of his or her hair-style, the neckband is in the shape of an Omega composed of lateral securing zones and a curved central part for free passage of the user's hair worn in a pony tail. The ends of the lateral securing zones of the neckband are joined to the adjustment means.

Abstract: A protective helmet is composed of an external crown made from plastic material, and a semi-rigid neckband adjustable by adjustment means. To ensure that the helmet is efficiently secured on the user's head regardless of his or her hair-style, the neckband is in the shape of an Omega composed of lateral securing zones and a curved central part for free passage of the user's hair worn in a pony tail. The ends of the lateral securing zones of the neckband are joined to the adjustment means.

Abstract: A protective helmet is composed of an external crown made from plastic material, and a semi-rigid neckband adjustable by adjustment means. At least one end of the neckband is joined to the crown by a sliding mechanical link comprising position indexing means controlled from a slide able to be moved from the outside in a slit of the crown. The indexing means are formed by a rack molded directly along with the crown.

Abstract: A double pulley device which has a pair of sheaves arranged in line inside a reverse U-shaped metal support flange-plate, each sheave being mounted rotating free on a fixed spindle of the flange-plate. At least one orifice for the passage of a snap-hook, is situated between the two spindles of the sheaves, so that the fixing point of the snap-hook is positioned above the point of contact of the sheaves with the cable. One of the wings of the flange-plate is arranged to enable the mobile finger of the snap-hook to be opened when the double pulley device is fitted onto the cable.

Abstract: A double pulley device comprises a pair of sheaves arranged in line inside a reverse U-shaped metal support flange-plate, each sheave being mounted rotating free on a fixed spindle of the flange-plate. At least one orifice for the passage of a snap-hook, is situated between the two spindles of the sheaves, so that the fixing point of the snap-hook is positioned above the point of contact of the sheaves with the cable. One of the wings of the flange-plate is arranged to enable the mobile finger of the snap-hook to be opened when the double pulley device is fitted onto the cable.