ghk -cu peptide GHK-Cu Scalp Solution GHK-Cu Peptides Before and After:
Description
Step 7 Attach a New Sterile Needle Screw a new sterile needle onto the end of the cartridge holder

Pennone V, Angelini E, Sarlah D, Lovati AB

I did google them and saw good reviews on Redditt prior to ordering

In that case, injections are not appropriate