White nylon plastic with a matte finish and slight grainy feel.
This is four cases for a Geodimeter battery 571 202 310. Can be used on Trimble radios also. It is for a light weight option to the heavy batteries. 10 AA rechargeable NiMH will make the radio last all day and use my bracket to connect to a good R/C car charger and it is a much better system than stock.