Related Clues:

• Alphabet trio
• 6 on the dial
• Touch-tone 4
• Four, on the phone
• Phone trio
• Alphabetical sequence
• 4, on a phone
• 6, on a phone
• Alphabet run
• Phone button trio
• Telephone trio
• 4 on a phone
• Alphabetic trio
• Phone-dial trio
• Sequence associated with 6