The Office of Defects Investigation (ODI) was in contact with a fleet that experienced multiple incidents of driver and passenger seatbelt buckle assemblies failing to unlatch.The seatbelts, manufactured by Taizhou TIANDA Rope and Belt Co, are original equipment on certain Stallion 900 motorcoaches.Preliminary evaluation suggested that two significantly different buckle assembly designs exist for a single part number 67RB1-04021.At the time of this investigation, failures appear to be limited to the earlier design. Shortly after opening this investigation, Taizhou Tianda Rope & Belt Co. Ltd decided to recall the earlier design buckles with safety recall 15E-016.An information request letter was not delivered before the recall was announced.Based on this action by the manufacturer, this investigation is closed.The ODI reports cited above can be reviewed at www-odi.nhtsa.dot.gov/owners/SearchNHTSAID under the following identification (ODI) numbers: 10631019, 10632409, 10633199 and 10633213.