Abstract: A boot has two fixed portions (3, 4 ) formed with openings (1,2) wherein inner surfaces (3a, 4a ) of at least either of the fixed portions (3, 4) are provided with lip portions (5) in which a rising angle (A1) of a slant on the inside of the boot in an axial section of the boot is larger than a rising angle (A2) of a slant on the outside of the boot.

Abstract: A sealing cover fitted on a coupling which connects an input shaft (1) and an output shaft (2) to each other for relative movement as in a U-joint including an outer member (3) having an outer spherical surface (3a) and connected to one of said shafts (2), comprises a first spherical shell (4) having an outer part made partly of a low flexibility material and having an inside part spherical surface slidably fitted on the outer spherical surface (3a), and a part spherical channel (7) open at the end of the shell near the other of the shafts (1), a second part spherical shell (8) slidably inserted at one end thereof into the channel (7) and fitted at the other end thereof on the shaft (1), a first sealing portion provided near one end of the first shell (4) in contact with the outer surface (3a) of the outer member (3), and a second sealing portion (10) provided near the other end of the first shell in contact with the outer part spherical surface (8c) of the second shell (8).