Used in various Bachmann engines including but not limited to:
HO 4-8-2 Heavy Mountain
HO 70 Ton Diesel
HO Alco 2-6-0
HO Chuggington
HO DD40AX
HO Donald & Douglas
HO FT/F7/F9
HO Northern
HO Shay
Large Scale 4-6-0
Large Rail Truck
HO S4
Please see specific engine diagrams for exact locations