You will receive 4 bottles of Silver Testing Acid, used to determine the Silver content of the piece being tested. · Each bottle has 1/2 fl oz of acid. · The sturdy plastic bottles maximize safety and allow the user to easily squeeze out one drop at a time. · All bottles have different cap colors to help keep acid karats organized easier · Latex Gloves are recommended with the use of any testing acids for safety · testing instructions included · black testing stone is recommended (sold separate from acids) ·