JBL Pro Sound with punchy bass delivers big sound in a small speaker. Up to 7 hours of battery life on a single charge. Playtime Boost - prolong playtime by adding up to 2 hours to battery life. IP67 Water and dustproof to handle a poolside party or seaside picnic. Pair two Go 4s for stereo sound or use Auracast. JBL Portable app. Incorporates post-consumer recycled plastic. Packaged in FSC-certified paper with soy ink. Rated output power: 4.2W RMS. Includes USB charging cable. Comes in a set of 2.