Good airbox with duct from a from a 1976 El Tigre 500. Online parts lookup shows this was on:  Part Number: 0109-863
Replaces 0109-773
1977 EL TIGRE 5000 - ENGINE AND RELATED PARTS
1977 EL TIGRE 4000 - ENGINE AND RELATED PARTS
1977 PANTERA F/A - ENGINE AND RELATED PARTS
1978 PANTERA F/A - ENGINE AND RELATED PARTS
Replaced by 0109-863
1976 PANTERA - ENGINE AND RELATED PARTS
1976 CROSS COUNTRY CAT - ENGINE AND RELATED PARTS
1976 EL TIGRE 500 - ENGINE AND RELATED PARTS