I have noticed on a number of web forums that there is significant interest in the specifications for the Universal Attachment Mount. This specification was published by the Society of Automotive Engineers (SAE) in June 2000 as Earthmoving Machinery - - Coupling of Attachments to Skid Steer Loaders The International Organization for Standardization (ISO) has also published this standard as 24410 in 2005. The specification actually describes the area that is reserved for the loader side of the attachment, which then tells you how to wrap an attachment mount around it. The SAE specification is Metric. If you would like a copy, here it is in Adobe format -- SAE_J2513.pdf This file has an additional image with all measurements converted to the nearest 16th inch.