Related Clues:

• Over 21s with no white socks knows the price of everything
• It stores information about retail costs, primarily in black lines
• Electronic providers of price and inventory information
• Parallel bars?
• Sets of lines on lines
• Stock control marking
• Strips for a price?
• Pub rules may be scanned
• Stock item marker
• Their lines allow readers to identify what's in store
• A little reading at the supermarket checkout?
• No jeans perhaps if you want a drink from product lines?
• Brocade (anag.)
• Checkout lines
• Check out lines excluding fish eaters primarily