TDS Pen Meter - Third Wave Water hario The Black Big Joe Knob

The Black Big Joe Knob is made from 100% Real Oak Wood and has been lacquered black

Compatible with standard V60 paper filters

Adventure-Proof Design

this caters for both solo and social tea enthusiasts

Bruer Spectrum Cone Filters #2

TDS Pen Meter - Third Wave Water hario The Black Big Joe KnobThird Wave Water have made their very own TDS Meter Pen, these TDS Meters measure the Total Dissolved Solids in a liquid and are an essential to have on hand when making your own brew water for coffee! Building water recipes from scratch or testing your water to see how much mineral content is super important, TDS or Total Dissolved Solids refers to the entire amount of minerals and particles dissolved in your liquid. While this doesn't tell you what