Unusual types of gramophone records Sievey. Chocolate records about three inches in diameter, and small players made for them, were marketed as a novelty in Europe in 1903–1904. After a record wore out or ceased to amuse, it could be eaten. In 1973, the Kingdom of Bhutan issued several unusual postage stamps that are playable miniature phonograph records. These thin plastic single-sided adhesive-backed 33 RPM discs feature folk music and tourism information. Not very practical for actual postal use and rarely seen canceled, they were designed as revenue-generating novelties and were initially scorned as such by most stamp collectors. Their small diameters (approximately 7 and
Gear inches of 27 x 1¼" (ETRTO 630). Strictly speaking, the rolling diameter of a 700c wheel may be significantly higher or lower than 27", depending on the tire size, e.g. nearly 27.5" for a 700x38 tire, or just over 26" for a 700x20 tire. This can be the source of some confusion when comparing gears unless it is clear whether gear inches have been calculated using the actual wheel size or a conventionalised 27". One way to estimate wheel diameter is to add twice the nominal tyre cross-section to the rim diameter. For example, consider a 700c × 23 mm tire,