What's the difference between the 316 and 304/321 plates?
|316 vs 304/321|
|Avg # of sessions per set*||30-40||30-40|
|Avg cost per session||$2.75||$3.72|
|Recommended session length||30 min||20 min|
|Overall session result||Same||Same|
*Because of varying water qualities, there is no guarantee on the number of sessions per set of plates you will receive.