Related Clues:

• Contents of a flickering sign, at times
• Rare gas
• You can make light of it
• Sign light
• 50-50 test guess
• Wayne's ''___ Grit''
• Diner sign filler
• Advertising sign gas
• Downtown sign
• An 1898 discovery
• Ginza light
• Gaseous attention-getter
• Fifty-fifty test choice
• Shade of blue?
• Strip lighting?