best length gaining protocol

2 days on 1 off vs 5 on and 2 off what do you think?

It’s all personal preference, but knowing how your penis reacts negatively and positively to things is a good thing to keep in mind and remember when adjusting and adding stuff to your routine. From those two choices I would suggest 2 on 1 off for beginners and 5 on 2 off for people with a more heavy routine, but like I said before it all comes down to your personal preference in the end, you know your penis better than anyone else so pay attention, be patient and be consistent. I hope this helped :)