Note 7: Inventory and Spare Parts
Inventory and spare parts as of December 31, 2007 and 2006, comprised the following:
| December 31, | |||
| 2007 | 2006 | ||
| Spare parts for base stations | $52,069 | $78,120 | |
| SIM cards and prepaid phone cards | 33,315 | 34,611 | |
| Handsets and accessories | 18,263 | 25,458 | |
| Advertising materials | 7,802 | 9,021 | |
| Other materials | 29,483 | 49,055 | |
| Total inventory and spare parts | $140,932 | $196,265 | |
Other materials mainly consist of stationery, fuel and auxiliary materials. Obsolescence expense for the years ended December 31, 2007, 2006 and 2005, amounted to $nil, $nil and $9,112, respectively, and was included in general and administrative expenses in the accompanying consolidated statements of operations. Spare parts for base stations included in inventory are expected to be utilized within the next twelve months after the balance sheet date.