slips 1/8 IPS x  1/4 IPS w/side hole. 
Unfinished brass coupling that is 5/8" diameter and 5/8" tall with 3/8" hole on top that slips 1/8 IPS pipe and 1/2" threaded bottom hole that works with 1/4 IPS pipe. 
It has side hole with 8-32 threads. 
$2 minimum charge orders less than $20. 
$.50 packing charge for each parts box.