The ornamental design for a men's underwear, as shown and described.
1. Men's underwear
1.1 : Perspective
1.2 : Front
1.3 : Back
1.4 : Top
1.5 : Bottom
1.6 : Left
1.7 : Right
1.8 : Exemplary perspective
1.9 : Exemplary perspective
The design has a protruded part attached to an opening provided at the front part of the men's underwear; penis and scrotum can be accommodated inside the protruded part by which the contact with other skins including the groin can be prevented; the front end of the protruded part are open so that the permeability are improved and the humidity, skin ailment and odor are decreased; when urinating, men can prevent infection due to a contact between hands and penis by rolling up the open front end of the protruded part; fig. 1.8 is an exemplary perspective view showing that a mannequin forming no part of the claimed design wears the men's underwear; fig. 1.9 is an exemplary perspective view showing that a protruded part of the men's underwear is rolled up.