|Powers||Extracts grace from angels, archangels, Nephilim, and former vessels|
|Location/Owners|| Men of Letters Bunker|
|Episodes|| 9.11 First Born|
12.19 The Future
13.17 The Thing
According to this, we may be able to use the grace that remains inside you to track Gadreel.... If we can extract it.
Grace Extractors appear to be capable of extracting grace from any kind of celestial being, including angels and archangels. They appear to be used primarily to extract angelic grace for its use in spells and they appear to come in many forms. The Grace Extractor in the Men of Letters Bunker appears as an old medical syringe while one used by Asmodeus resembles a vintage veterinary syringe with a side plug that holds glass vials intended for containing the extracted grace.
The Grace Extractor first appeared as a metal syringe which was kept in the Men of Letters Bunker. This one was created by James Haggerty while he was in the Bunker observing the inner workings of angels. During his research, he created a tracking spell for angels along with the syringe with the purpose to extract angelic grace for the spell, but he never was able to test the theory before he retired.
While Sam and Castiel are looking for a way to locate Gadreel, Castiel comes across a file by James Haggerty titled "The Inner Workings of Angels." Haggerty discovered that when angels leave their vessels, they leave behind a piece of themselves, including a portion of their grace. In Sam's case, the grace resonating within him is fading each time he gets healed. Castiel is able to locate the Men of Letters' instructions on how to use extracted grace to perform an angelic tracking spell that can find Gadreel, including information on a syringe that can extract the grace remnants from the former vessel.
Sam and Castiel locate the syringe and perform the extraction in the Bunker's laboratory. Unfortunately, Sam's body begins to revert to the state that it was in before Gadreel possessed him. Despite his worries about Sam, Castiel continues to push the needle in deeper to remove the grace. Sam's condition starts to get worse and Castiel tries to remove the syringe, but Sam keeps pulling it back in place, stating that his life is no more valuable than Castiel's, Dean's, or Kevin's lives. Castiel soon removes the syringe and heals Sam's wounds completely, resulting in erasing the remaining fragments of Gadreel's grace, despite not extracting enough to sufficiently cast the spell, stating that they have to work with what they currently have and that nothing is worth losing Sam. The contents of the syringe are dumped into the bowl while attempting to perform the spell, but there is not enough grace, leaving the spell ineffective.
After searching for a way to track down Dagon, Sam theorizes that Nephilim are merely human souls infused with angelic grace. He believes that if they removed the grace from Kelly Kline's baby, then it would render it human and it wouldn't mean killing either of them. When they explain their plan to Castiel and Kelly, Castiel objects on the grounds that the prior grace extraction nearly killed Sam. After being influenced by the unborn Nephilim's powers, Kelly refuses to let them do it because she wants her baby to be born with all its powers.
Using his own grace extractor, in the form of a veterinary syringe, Asmodeus has been stealing archangel grace from Gabriel who was imprisoned in the Needham Asylum. Ketch barges into the throne room and watches him siphoning the grace from Gabriel's neck and injecting it into his own arm. With the archangel grace, Asmodeus has been able to gain new special abilities and even overpower Ketch with ease. Asmodeus later uses it to inject more grace into his arm before leaving a wounded Ketch alone with Gabriel. Ketch uses the opportunity to break free from his restraints, rescue Gabriel, acquire the archangel blade and the other vials of Gabriel's previously-extracted grace, and escape to the Men of Letters Bunker.
Gabriel extracts some of his grace for the spell in private, but comes back with a relatively small amount, which is not enough to effectively open the rift. While the syringe isn't seen, it can be assumed that he used Haggerty's grace extractor.