.ProductID              = 0x204A,
        .ReleaseNumber          = VERSION_BCD(01.00),
 
-       .ManufacturerStrIndex   = 0x01,
-       .ProductStrIndex        = 0x02,
+       .ManufacturerStrIndex   = STRING_ID_Manufacturer,
+       .ProductStrIndex        = STRING_ID_Product,
        .SerialNumStrIndex      = NO_DESCRIPTOR,
 
        .NumberOfConfigurations = FIXED_NUM_CONFIGURATIONS
                        Size    = sizeof(USB_Descriptor_Configuration_t);
                        break;
                case DTYPE_String:
-                       if (!(DescriptorNumber))
+                       if (DescriptorNumber == STRING_ID_Language)
                        {
                                Address = &LanguageString;
                                Size    = LanguageString.Header.Size;
                        }
-                       else if (DescriptorNumber == 0x01)
+                       else if (DescriptorNumber == STRING_ID_Manufacturer)
                        {
                                Address = &ManufacturerString;
                                Size    = ManufacturerString.Header.Size;
                        }
-                       else if (DescriptorNumber == 0x02)
+                       else if (DescriptorNumber == STRING_ID_Product)
                        {
                                Address = &ProductString;
                                Size    = ProductString.Header.Size;