Philips S7807 is the one that always has your back. Solidly built and rigorously tested to meet an IP67 rating, this portable Bluetooth speaker is more than rugged enough to cope with a day at the beach. It delivers great sound, whether perched on a paddle board, hung from a tent, or clipped to one's backpack halfway up a dusty mountain trail. Two 70 mm woofers and two tweeters offer rich bass texture, and the power bank function lets you charge connected devices without stopping the music. You can connect it to your smartphone and tablet simultaneously, or pair it with an identical twin for room-rocking stereo. 24hrs of playtime is more than enough for a walk in the woods or a trip to the lake. Just grab and go.