The center looks similar to crossbones and is perfect with the skull horn button.

Includes two horn buttons and other detailing items with instructions.

Horn button can be a standard round button or a skull button.

The photo above makes the outer rings look like rubber, but they are actually stainless steel.  This can be left as is or painted. 

Makes one complete steering wheel.

Here's a photo of a similar steering wheel on a Detail Master steering column

Photo etched parts By Detail Master, 1/24-1/25 scales.