One Ruler to Rule them All. A PCB ruler with useful conversions and information.
RUL-0001 Alpenglow Industries, Tools
Battery Holder 2xAA with Cover and Switch - JST Connector - PRT
6 Digital Calipers - TOL-10997 - SparkFun Electronics
Friday Product Post: Balancing the Scales - News - SparkFun
SparkFun Block for Intel Edison - ADC
Friday Product Post: Balancing the Scales - News - SparkFun
SparkFun Electronics 的How to Use a Ruler 規格書
How to Use a Ruler
How to Use a Ruler - SparkFun Learn