The S.P.I.N. Tech was first used by War Machine in an attempt to arrest Spider-Man for non-compliance to the Super-Human Registration Act. When Spider-Man was fighting the latest incarnation of the Sinister Syndicate, they were all hit by the nanobots except for Spider-Man. When War Machine was about to shoot Spider-Man, he clogged his gun thus firing back at War Machine, shutting his armor down temporarily.
Before the events of World War Hulk, Iron Man used the S.P.I.N. tech to She-Hulk when she found out that the Illuminati were the ones that banished her cousin, the Hulk, in space. Iron Man later disabled the nanobots inside She-Hulk so she could help him against her cousin's rampage upon his return.
When Iron Man fought the Hulk, he tried to use the S.P.I.N. tech against him but found out that they were ineffective because the S.P.I.N. tech was not present because the Initiative cadet, Hardball stole it earlier. Hardball then gave the S.P.I.N. tech to a high ranking Hydra official to be used against the heroes. When the Shadow Initiative infiltrated the Hydra base, Hardball destroyed all of it except for one that he kept for himself. Unfortunately, it was stolen by former SHIELD agent, Carmilla Black, hired by Sasha Kravinoff.
The S.P.I.N. Tech are nanobots developed by Iron Man that is used to depower individuals with superpowers and also disable technology-based individuals such as War Machine. The nanobots are loaded to a adamantium-tipped tranquilizer shots and can be fired in any firearm. The tech can also be DNA-specific to a certain target to prevent friendly-fire and can be remotely shut down which means that those shot be the nanobots can regain their powers back. When Iron Man had worries about the effect of the nanobots on the Hulk, it could mean that the S.P.I.N. tech is not effective to superhumans that can increase their powers.