Effects Loop Switch Boxes Project History file 2014-06-18 - Started History File. 2014-09-02 - Added a link to the Dual Effects Loop kit and corrected some wording on this page. 2017-01-25 - Added standard dual loop 2019-08-25 - Updated single loop labeling to "Send" & "Return". Added Buffer versions to single and double loop switche options. Also added booster version to double loop options. 2019-08-27 - Added another Buffer wiring option for the Loop box. Added User Manuals for the Loop Box and the Dual Loop Box.