122503A1 Inner Dipper Arm Fits Case 580L, 580MOne New Aftermarket Replacement Inner Dipper Arm Fits Case 580L and 580M Backhoe Loaders This aftermarket replacement inner dipper arm (also called an inner dipper stick or crowd arm) is the inner telescoping tube of the Extendahoe extendable dipper assembly on Fits Case (Fits Case International Harvester) 580L and 580M backhoe loaders. It slides within the outer dipper stick to extend reach and is a core structural component of the backhoe's