Endless conveyor belt for a conveyor device, said conveyor belt comprises a belt body with a width (L) and a longitudinal median plane (X), said belt body comprises a top face intended to receive products to be transported, an opposite bottom face , intended to cooperate with drive means constituting said conveyor device , and two side edges parallel to each other, - said belt body is transversely deformable between a flat configuration, at rest, and a tubular or at least substantially tubular configuration, wherein the two side edges are connected edge to edge, - said belt body comprises two transition regions (B) extending longitudinally over said width (L) of said belt body , the two transition regions (B) being located 1/4 or approximately 1/4 of said width (L), on either side of said median plane (X), - said transition regions (B) define between them a central belt portion (C), as well as two side belt portions (D) located between each of them and the nearby belt side edge , - the conveyor belt comprising an upper layer made of a first material having a first hardness and forming said top side , and a lower layer made of a second material having a second hardness and forming said bottom face , the second hardness of said lower layer being greater than the first hardness of said upper layer , - said lower layer comprising softening recesses , the lower layer comprising a constant or substantially constant thickness, without taking account of said softening recesses , - the conveyor belt being characterised in that at least one thickness (F) of said side belt portions (D) is greater than at least one thickness (G) of said central belt portion (C), forming at least one overthickness region on each of said side belt portion (D), said overthickness region of each side belt portion (D) protruding from the top face of the conveyor belt so as to form a relief, the top face being flat between the overthickness regions . - said belt body is transversely deformable between a flat configuration, at rest, and a tubular or at least substantially tubular configuration, wherein the two side edges are connected edge to edge, - said belt body comprises two transition regions (B) extending longitudinally over said width (L) of said belt body , the two transition regions (B) being located 1/4 or approximately 1/4 of said width (L), on either side of said median plane (X), - said transition regions (B) define between them a central belt portion (C), as well as two side belt portions (D) located between each of them and the nearby belt side edge , - the conveyor belt comprising an upper layer made of a first material having a first hardness and forming said top side , and a lower layer made of a second material having a second hardness and forming said bottom face , the second hardness of said lower layer being greater than the first hardness of said upper layer , - said lower layer comprising softening recesses , the lower layer comprising a constant or substantially constant thickness, without taking account of said softening recesses , - the conveyor belt being characterised in that at least one thickness (F) of said side belt portions (D) is greater than at least one thickness (G) of said central belt portion (C), forming at least one overthickness region on each of said side belt portion (D), said overthickness region of each side belt portion (D) protruding from the top face of the conveyor belt so as to form a relief, the top face being flat between the overthickness regions . <EOS>