What is the bulge lug nut?

The following photos are two different types of tire nuts, the right one is bulge lug nut 

Which is better?

Please refer to the following figure:

Both of these products are 13/16 "HEX, 1.4" Length, Acorn Seat

Acorn Bulge Lug Nut, higher cone, cone and hub contact surface is greater, so the installation is more stable.

The relation between diameter of bulge, cone, and hub base:

1. The larger diameter of the bulge, the higher the cone, so that more contact surface with the hub base, and more firm.

For example,

When the diameter of bulge is 22mm, the height of the cone is only 6.14mm,

When the diameter of bulge is 23mm, the cone height is 7.02mm

When the diameter of bulge is 24mm, the height of cone is 7.89mm,

So the larger the diameter of Bulge, the larger the cone and the stronger the installation.

Note that some factories will reduce the diameter of bulge in order to jerry-build, so as to reduce the material cost, but the cone will be very short.

2. The outer diameters of the bulge are the same, if the thread holes are different, the height of the cone will be different.

Such as the following drawing:

The diameters of bulge are all 23mm

When the thread is 12x1.50, the diameter of the bottom is 15mm and the height of the cone is 7.02mm

When the thread is 14x1.50, the diameter of the bottom is 17mm and the height of the cone is only 5.26mm

Therefore, the larger the threaded hole, the shorter the cone.

Note that in order to cut corners, some factories will increase the diameter of bottom to reduce the material cost, but the cone will be very short.