diff --git a/.DS_Store b/.DS_Store
index ac96bd15..94ec7715 100644
Binary files a/.DS_Store and b/.DS_Store differ
diff --git a/src/main/kotlin/com/ecwid/apiclient/v3/converter/FetchedProduct.kt b/src/main/kotlin/com/ecwid/apiclient/v3/converter/FetchedProduct.kt
index 2a7407d5..82487f6b 100644
--- a/src/main/kotlin/com/ecwid/apiclient/v3/converter/FetchedProduct.kt
+++ b/src/main/kotlin/com/ecwid/apiclient/v3/converter/FetchedProduct.kt
@@ -72,6 +72,7 @@ fun FetchedProduct.toUpdated(): UpdatedProduct {
 		minPurchaseQuantity = minPurchaseQuantity,
 		maxPurchaseQuantity = maxPurchaseQuantity,
 		reviewsCollectingAllowed = reviewsCollectingAllowed,
+		batteryIncluded = batteryIncluded,
 	)
 }
 
diff --git a/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/request/UpdatedProduct.kt b/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/request/UpdatedProduct.kt
index 9e4675af..f2075d0e 100644
--- a/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/request/UpdatedProduct.kt
+++ b/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/request/UpdatedProduct.kt
@@ -72,6 +72,7 @@ data class UpdatedProduct(
 	val minPurchaseQuantity: Int? = null,
 	val maxPurchaseQuantity: Int? = null,
 	val reviewsCollectingAllowed: Boolean? = null,
+	val batteryIncluded: Boolean? = null,
 ) : ApiUpdatedDTO {
 
 	data class Ribbon(
diff --git a/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/result/FetchedProduct.kt b/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/result/FetchedProduct.kt
index f0c31b35..b1971dd0 100644
--- a/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/result/FetchedProduct.kt
+++ b/src/main/kotlin/com/ecwid/apiclient/v3/dto/product/result/FetchedProduct.kt
@@ -140,6 +140,7 @@ data class FetchedProduct(
 	val minPurchaseQuantity: Int? = null,
 	val maxPurchaseQuantity: Int? = null,
 	val reviewsCollectingAllowed: Boolean? = null,
+	val batteryIncluded: Boolean? = null,
 	val rating: Double? = null,
 	val reviewsModerated: Int? = null,
 	val reviewsPublished: Int? = null,
diff --git a/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt b/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt
index d87b640a..456df987 100644
--- a/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt
+++ b/src/test/kotlin/com/ecwid/apiclient/v3/entity/CustomersTest.kt
@@ -13,6 +13,7 @@ import com.ecwid.apiclient.v3.exception.EcwidApiException
 import com.ecwid.apiclient.v3.util.randomAlphanumeric
 import com.ecwid.apiclient.v3.util.randomBoolean
 import com.ecwid.apiclient.v3.util.randomEmail
+import com.ecwid.apiclient.v3.util.randomNumeric
 import org.junit.jupiter.api.Assertions.*
 import org.junit.jupiter.api.BeforeEach
 import org.junit.jupiter.api.Disabled
@@ -419,7 +420,7 @@ private fun generateTestCustomerForCreate(customerGroupId: Int?): UpdatedCustome
 			generateShippingAddress(),
 			generateShippingAddress()
 		),
-		taxId = randomAlphanumeric(8),
+		taxId = randomNumeric(8),
 		taxIdValid = randomBoolean(),
 		taxExempt = randomBoolean(),
 		acceptMarketing = randomBoolean(),
@@ -444,7 +445,7 @@ private fun generateTestCustomerForUpdate(
 			generateShippingAddress(oldShippingAddresses?.get(2)?.id),
 			generateShippingAddress(oldShippingAddresses?.get(3)?.id)
 		),
-		taxId = randomAlphanumeric(8),
+		taxId = randomNumeric(8),
 		taxIdValid = randomBoolean(),
 		taxExempt = randomBoolean(),
 		acceptMarketing = randomBoolean(),
diff --git a/src/test/kotlin/com/ecwid/apiclient/v3/rule/nullablepropertyrules/FetchedProductRules.kt b/src/test/kotlin/com/ecwid/apiclient/v3/rule/nullablepropertyrules/FetchedProductRules.kt
index 4bd20bc2..2842314d 100644
--- a/src/test/kotlin/com/ecwid/apiclient/v3/rule/nullablepropertyrules/FetchedProductRules.kt
+++ b/src/test/kotlin/com/ecwid/apiclient/v3/rule/nullablepropertyrules/FetchedProductRules.kt
@@ -73,6 +73,7 @@ val fetchedProductNullablePropertyRules: List<NullablePropertyRule<*, *>> = list
 	AllowNullable(FetchedProduct::rating),
 	IgnoreNullable(FetchedProduct::relatedProducts),
 	AllowNullable(FetchedProduct::reviewsCollectingAllowed),
+	AllowNullable(FetchedProduct::batteryIncluded),
 	AllowNullable(FetchedProduct::reviewsModerated),
 	AllowNullable(FetchedProduct::reviewsPublished),
 	IgnoreNullable(FetchedProduct::ribbon),
diff --git a/src/test/kotlin/com/ecwid/apiclient/v3/util/RandomUtils.kt b/src/test/kotlin/com/ecwid/apiclient/v3/util/RandomUtils.kt
index c5ea6fd1..422b7e5a 100644
--- a/src/test/kotlin/com/ecwid/apiclient/v3/util/RandomUtils.kt
+++ b/src/test/kotlin/com/ecwid/apiclient/v3/util/RandomUtils.kt
@@ -62,6 +62,14 @@ internal fun randomAlphanumeric(size: Int): String {
 		.joinToString("")
 }
 
+internal fun randomNumeric(size: Int): String {
+	val digits = ('0'..'9').toList()
+	return (1..size)
+		.map { Random.nextInt(0, digits.size) }
+		.map(digits::get)
+		.joinToString("")
+}
+
 internal inline fun <reified E : Enum<E>> randomEnumValue(vararg exclude: E): E {
 	return E::class.java.enumConstants
 		.toSortedSet()