Abstract: A golf bag with a base having protrusion forming regions at a first section ranging from 30 to 60 degrees from a reference line, a second section ranging from 120 to 150 degrees from the reference line, a third section ranging from 210 to 240 degrees from the reference line, and a fourth section ranging from 300 to 330 degrees from the reference line. At each of the protrusion forming regions, one or more protrusions are formed to prevent the golf bag from rotating and falling over. A pair of tangents drawn from two of the protrusions in the front-rear direction and a pair of tangents drawn from two of the protrusions in the lateral direction pass outside of a base peripheral edge. Auxiliary protrusions may also be formed on the base at the positions of 90 degrees and 270 degrees from the reference line. All tangents linking the adjacent protrusions and all tangents linking the adjacent protrusion and auxiliary protrusion may pass outside of the base peripheral edge.

Abstract: A golf bag with a base having protrusion forming regions at a first section ranging from 30 to 60 degrees from a reference line, a second section ranging from 120 to 150 degrees from the reference line, a third section ranging from 210 to 240 degrees from the reference line, and a fourth section ranging from 300 to 330 degrees from the reference line. At each of the protrusion forming regions, one or more protrusions are formed to prevent the golf bag from rotating and falling over. A pair of tangents drawn from two of the protrusions in the front-rear direction and a pair of tangents drawn from two of the protrusions in the lateral direction pass outside of a base peripheral edge. Auxiliary protrusions may also be formed on the base at the positions of 90 degrees and 270 degrees from the reference line. All tangents linking the adjacent protrusions and all tangents linking the adjacent protrusion and auxiliary protrusion may pass outside of the base peripheral edge.

Abstract: A golf bag with a base having protrusion forming regions at a first section ranging from 30 to 60 degrees from a reference line, a second section ranging from 120 to 150 degrees from the reference line, a third section ranging from 210 to 240 degrees from the reference line, and a fourth section ranging from 300 to 330 degrees from the reference line. At each of the protrusion forming regions, one or more protrusions are formed to prevent the golf bag from rotating and falling over. A pair of tangents drawn from two of the protrusions in the front-rear direction and a pair of tangents drawn from two of the protrusions in the lateral direction pass outside of a base peripheral edge. Auxiliary protrusions may also be formed on the base at the positions of 90 degrees and 270 degrees from the reference line. All tangents linking the adjacent protrusions and all tangents linking the adjacent protrusion and auxiliary protrusion may pass outside of the base peripheral edge.

Abstract: A baseball or softball bat capable of increasing the hit distance of a ball and reducing the manufacturing cost can be obtained. A baseball or softball bat (1) including a hitting portion (2), a taper portion (3), and a grip portion (4) has a tubular member (6a, 6b) which includes an outer circumference plane (25) extending from the hitting portion (2) to the grip portion (4) and an inner circumference plane (26) located inside the outer circumference plane (25) and extending from the hitting portion (2) to the grip portion (4), and a metal tubular member (8) which is placed between the outer circumference plane (25) and the inner circumference plane (26) at least in the hitting portion (2), the metal tubular member (8) having a weak boundary layer (7) formed on its surface.

Abstract: A sweet spot 3 of an impact portion 2 has a smaller diameter than the other portions of the impact portion 2, whereby the impact portion 2 has an intermediate tapering shape in the longitudinal direction. Thus, even if hit with a portion at some distance from the sweet spot, rebound performance is not significantly reduced. Therefore, a bat having a large sweet area and capable of reducing the occurrence of foul balls is obtained.

Abstract: In this portless type master cylinder device, a cylinder bore is formed in a body thereof, and a piston member is fitted in the cylinder bore and is slidably movable from an initial axial position therein and defines a pressure chamber in cooperation with the cylinder bore. An intake valve communicates between the cylinder chamber and the fluid reservoir via a fluid flow path, and is opened when the piston member is in its initial axial position while it is closed when the piston member moves through more than a determinate relatively small axial distance from its initial axial position.