What are the product specifications of *RWK14, & what does this wheel kit include?

Product Description: 15" x 7" / 15" x 8" Mixed Rally Wheel Kit with Sombrero Style Chevrolet Motor Division Caps

Kit Includes:

• 2 - 15" x 7" Rally Wheels
• 2 - 15" x 8" Rally Wheels
• 2 - 15" x 7" Stainless steel trim rings
• 2 - 15" x 8" Stainless steel trim rings
• 4 - Sombrero style Chevrolet Motor Division center caps
• 20 - Lug nuts
• 4 - Wheel locks
• 1 - Wheel lock key
• 4 - Valve stems

Wheel Specifications:

• Wheel size: 15" x 7"
• Lug pattern: 5 x 4-3/4"
• Backspacing: 4-1/4"
• Offset: +6mm</li></ul><ul>

• Wheel size: 15" x 8"
• Lug pattern: 5  x 4-3/4"</li>
• Backspacing: 4-1/4"</li>
• Offset: -6mm