It is designed to fit most of Hornby's coupling rod bolt heads. The Hornby R913 Con Rod Nut Spanner is a precious tool to have for coupling and wheel maintenance. The product is double-ended, with a different size spanner at each end.
HORNBY R913 Con Rod Nut Spanner - Double Ended
Hornby R913 OO Gauge Con Rod Nut Spanner-Double Ended
Hornby R913 Con Rod Nut Spanner - Double Ended OO Gauge
CON ROD TOOL SPANNER - Double Ended Track Accessories HORNBY Tool Box R913
Hornby R913 Con Rod Nut Spanner Double End