Boot (4) protecting the male (2) and female (3) elements of a transmission joint (1) and respectively formed, in the case of one of them (2), of a transmission shaft (23) with radial arms (21) bearing rollers (22), and, the other of them (3), of a housing able to at least partially house said rollers (22) that can be inserted into the housing via the open end (31) of said housing, said boot (4), which takes the form of an elongate hollow body (41) through which the shaft (23) can pass having one of its ends, referred to as the first end (42) that can be secured to said shaft (23) and the other of its ends, referred to as the second end (43), that can be positioned over the open end (31) of the housing such that the latter is nested therein with overlap. This boot has an internal peripheral shoulder (44), and that surface (441) of the shoulder (44) that faces toward the second end (43) of the boot (4) is equipped with at least two housings (4411) open in the direction of said second end (43), the inside of each housing forming a seat (4411) with concave seating surface able to form a surface that will accept a roller with bearing contact.