Thousandshores Inc via Amazon offers the Dr.Meter Moisture Sensor Hydrometer for $14.99. (Click on "Regular Price" on the right-hand side.) Coupon code "2SEGTJ2K" cuts it $8.49. Plus, Prime members bag free shipping. That's $22 off and the lowest price we could find. It measure soil's moisture content with ten scales. Deal ends August 15.