sparkThe Science Behind Spark. Spark Alners are made with TruGEN™, the latest innovation in clear alner material. Spark’s nearly invisible alners are clearer, more comfortable, and stain less than the leading alner brand.*Downloading. Get Spark from the downloads page of the project website. This documentation is for Spark version 3.5.5. Spark uses Hadoop’s client libraries for HDFS and YARN. Downloads