Related Clues:

• 20-20, say
• Slip preventer
• Porch item
• Tumbler's need
• Wrestling surface
• Haberdashery buy
• Gymnast's milieu
• 50-50, say
• It may be at your doorstep
• What 21-Across 51-Down is
• Have no loose ends?
• Floor covering
• Get even?
• Share first, e.g.
• Place to exercise