Kettlebells are wonderful tools for strength training. The Ultra Fitness Portable Sandbag Kettlebell is a soft one for those of you on the go. It has a maximum capacity of 30lbs, so you can just open fill up the removable liner with the amount of sand that fits your training routine.
The neat thing is you can take this kettlebell everywhere you go and fill it when you need to get a workout. It features 1600D Codura fabric, so it will last you for a while.