Extechs company website has it cheaper. I think its 99 was 10% when i looked 5to6 months ago. That ph meter is the ticket! Front row seat right there bud...BUY IT. You wont regret it. Keep the lens hydrated for it work right. If you notice it dry. Rehydrate it!!
Read the user manual on how to properly care for it and store it. Mine is a ph 100
That ph110 is a refillable one. I'd just stk with the ph100 not the 110 in that link