Related Clues:

• It might improve your focus
• Shooter's aiming aid
• Optometry concern
• "Outta ___!"
• Sniper's aid
• 25-Across aid
• Ending for micro- or oscillo-
• Copes with range
• The ability to see
• Faculty of vision
• Extent or reach
• Vision, ability to see
• The range of something, say an inquiry
• Sounds icy with this
• See how one may heave a deep breath before tea