Puberty blockers exist to give the option to change more time before puberty does significant alterations to a person.
Essentially, it buys time for younger trans people to be certain of their choices and minimize the (already remote) possibility of de-transitioning being needed.
There is also no evidence of any significant negative side-effects from the treatment.
Isn’t that a self-propelled artillery piece? I wanna say like an M109 or something