Start with the product and species, then add the dimensions, grade, quantity, moisture requirement and any treatment requirement. If the timber will be used for a specific manufacturing or packaging application, include that context as well.
Buyers should also state whether the requirement is one-time or regular, the preferred delivery timing and any origin preference. If the requirement is flexible, say which specifications may be adjusted and which are fixed.
The more complete the specification, the easier it is to identify relevant supply options and discuss commercial terms efficiently.