2.650", 3.03", or 3.110" Chain Case Boom

Head Shaft and Boom Replacement Parts for Models 25+4XP, 30+4, 40+4, RT360--2.65" Pitch Chain

Head Shaft and Boom Replacement Parts for Models DH4, DH4B, DH5--2.65" Pitch Chain

Head Shaft and Boom Replacement Parts for Direct Drive Models RT460, RT560 and RT660 Quad--2.65" Pitch Chain

Head Shaft and Boom Replacement Parts for Planetary Drive Models RT460 and RT560--2.65" or 3.11" Pitch Chain

Head Shaft and Boom Replacement Parts for Models RT660--2.65" or 3.11" Pitch Chain

Head Shaft and Boom Replacement Parts for Models RT660, 760, 860, RT960 and RT1160--3.03" or 3.11" Pitch Chain