AMI pH meters, I just checked mine out, between each number there are 4 little lines, which if I interpret that correctly that means a .2 difference There is enough space between the little lines so I can interpolate .2, .25 .3 .35 and .4 for example. Operation, Wet soil, wipe probe, insert into soil, rotate back and forth a 1/2 doz. times, wait one min. read scale. Remove probe and wipe off. Price under $20. Close enough for me.