### Clue: Check tip of electrode on top of sperm-producing glands (6)
### Answer: TESTES 
 ### Explanation: Definition: sperm-producing glands
  TEST(check,to confirm or explore) E(first, or last letter,tip of "electrode) **placed before**(on) S(first letter,top of "sperm" – the word doing double duty in wordplay and defn).  I don't know what to make of the surface – some form of sterilisation procedure? 🙂
Answer:  The glands in your family jewels.