I like my extension rings

Moved on from my simple rings to a set with electrical and mechanical coupling. This makes is a snap to do macro on my F5 for instance:

0068_Maco_AQS_400@250_F5_20131225_025

0068_Maco_AQS_400@250_F5_20131225_031

0068_Maco_AQS_400@250_F5_20131225_037

0068_Maco_AQS_400@250_F5_20131225_039