Jewish mans testicles. Originaly this joke created the word Jewbs, Q: "What do you call a Jewish womans boobs?" A: "Jewbs!" The name 'Jewbs" then inspired the naming of a jewish mans testicles, 'Jewbsticles'. A Jewish man has two jewbsticles (singular jewbsticle), they dangle from his jewsack.
When my sisters Jewish boyfriend goes swimming, he wears speedo's and you can clearly see the outline of his jewbsticles because they are tight and hug his crutch.