You want to use a 3cc syringe. Use a 20g to draw the oil into the barrel. Then switch to a 23-25g pin to inject. For someone that isn't over weight, you can usually hit glutes with a 1in pin. If you have some extra fat, go with a 1.5 in. In general, a 1.5in is the safer bet for glutes. You want to bury that shot and get it deep in the muscle. For delts and quads, you can use a 1in.
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