Chandler Ltd, 1977. 维基共享资源上的相关多媒体资源:線圈 Coil Inductance Calculator Online calculator for determining the inductance of single-layer and multilayer coils R. Clarke
Butterfly bend(英语:Butterfly bend) – connects two ends of rope Butterfly coil(英语:Butterfly coil) – a method for storing and transporting a climbing rope Butterfly