It's a nice 5-AA battery holder, with 5" leads and a 2.1mm DC barrel plug.
Need to add more voltage to your regular 4AA battery pack? Parallax has come up with this ingenious plug in module that adds a 5th module to your AA quad-pack holder.
This is a coin cell holder for the common CR2032 type battery. The holder has a neat pop-in, pop-out feature that makes changing the battery easy.
Need a tidy DC-to-DC converter? This SparkFun breakout board offers 6 amperes of conversion, taking any DC voltage between 4.5-14VDC, and turning it to a selectable voltage between 0.59 and 5.5VDC.
Switchable Voltage Divider is a voltage divider with switches. The switches can be used to control which resistors are used in the voltage divider.
The Dimension Engineering 5V switching regulator is a tight & tidy voltage regulator that offers great performance at an excellent price. Great for extending battery life!
The AnyVolt DC-DC converter is small, powerful, and very useful for applications needing efficient voltage switching. The guys as Dimension Engineering know their stuff!
Looking for a low, LOW voltage boost converter in a tidy package? Dimension Engineering's LVBoost is just the solution!