ph pen anyone have them

[fishguyxd]

Does anyone use them or know who has them for sale?
I searched ebay there there but prefer to buy local.

Buy the way how do you like them?

[fishguyxd]

bump

want to buy one
do they work just as well as a moniter?

[Joe Reefer]

I think using a monitor is better because all you have to do is look at it anytime of the day, and you know what your system is at. IMHO
As long as you calibrate it regularly.