See this good deal to get up to 30% Off | Cigar Oasis Caliber IV Slim Digital Hygrometer. The latest version of the acclaimed Caliber series from Western Humidor (now Cigar Oasis) Western Humidor has always been known as the maker of the most accurate hygrometers in the cigar industry and beyond. The Western Humidor Caliber was the original digital hygrometer for the cigar industry.