O Ring Splice
This is just a simple Jig to help splice O Rings. The slots in it are for O Ring sizes 1/8", 3/16", and 1/4".
http://ryanfabrications.blogspot.com/2015/03/piston-test-print.html
I do not certify any effective sealing pressure with O rings joined this way. I used this O rings to seal water at atmospheric pressure, you shouldn't risk it for anything that could cause injuries unless you are satisfied with how the system was made.