Abstract: In a 120- or 220-size roll film, a leader of a light-shielding paper has at least a hole to be engaged with a claw formed in a slit of a spool core. A pair of ribs are formed on an opposite wall of the slit from the claw. The ribs have a height larger than a thickness of the light-shielding paper plus a distance from a peak of the claw to the opposite wall, so that the ribs urge the leader toward the claw, and let the hole be caught on the claw. The claw has side projections which protrude in an axial direction of the spool core in proximity to the peak of the claw. Guide surfaces of the claw which face entrances of the slit are inclined toward each other, such that the hole caught on the claw is guided to be engaged with the side projections upon the leader being relatively moved away from the slit when the spool is rotated.