Possible Clues:

• Spiral lock of hair
• Lock of hair enclosed by adoring letter-writer
• Bit of a shock to call time after half a mile
• Covering letter features a butterfly
• Being on hand, allow it to be be on ahead
• Kind of curl - a tingler
• Twenty five allowed in lock
• A single curl
• Lock created obstruction, holding up band
• Tingler of a curl