A housing element for a writing instrument includes a hollow, sleeve-shaped, elongated base body having an opening for receiving the writing instrument or a pencil lead of the writing instrument at a first longitudinal end. The base body has a second longitudinal end, which is opposite the first longitudinal end, and has a retaining recess that is formed with a polygonal cross section for directly or indirectly retaining a bit in a rotationally fixed manner. A writing instrument including the housing element is also provided.

A composite writing implement according to an embodiment includes a barrel, writing shafts housed in the barrel, a cam main body including a cam projection, an end surface extending along the cam projection, and a latch recess provided in the cam projection, and sliders configured to be connected to respective rear ends of the writing shafts, and include a cam configured to be latchable to the latch recess, and have a sliding contact surface to be pressed against the end surface, wherein the end surface includes a first inclined portion that is positioned on the front end side of the cam projection and is inclined by a first incline angle, and a second inclined portion that is positioned further toward the rear end side of the cam projection than the first inclined portion, and is inclined by a second incline angle that is larger than the first incline angle.

A multifunction writing instrument comprising a body extending along an axis and receiving at least two writing elements, each writing element comprising a writing tip and being movable between a protruded position in which the writing tip extends out of the body and a retracted position in which the writing tip is retracted within the body, and an actuating mechanism comprising a spinner configured to move one of the writing elements at a time, one after the other, from the retracted position to the protruded position, a ratchet receiving the spinner, and a single button configured to actuate the actuating mechanism.

Provided are an erasing implement and a writing implement equipped with the erasing implement, the erasing implement being capable of erasing writing regardless of the type of ink or lead of the writing implement, even writing with thermochromic ink or writing with pencil lead. The erasing implement is equipped with a first erasing member for erasing writing with thermochromic ink and a second erasing member for erasing writing of types other than thermochromic ink, and is configured by covering the outer surface of the second erasing member with the first erasing member.