First go to https://jlcpcb.com
Create your account
To order prints go to:
https://jlc3dp.com/?source=JLCPCB-top-productbar

download DOUBLER BRACKET V2.2- ASA.stl_.zip
https://bbmpulser.org/wp-content/uploads/2024/12/DOUBLER-BRACKET-V2.2-ASA.stl_.zip
then unzip your .stl file and upload it to https://jlc3dp.com/
Please select:
3D Technology - FDM (Plastic)
Material - ASA 
Color - White or Black, your choice

let me know if you have any questions
support@bbmpulser.org