diff --git a/Tests/DeviceFamilyTests.swift b/Tests/DeviceFamilyTests.swift
index c8139ab..8a83d79 100644
--- a/Tests/DeviceFamilyTests.swift
+++ b/Tests/DeviceFamilyTests.swift
@@ -41,6 +41,11 @@ class DeviceFamilyTests: XCTestCase {
         XCTAssert(deviceFamily == .iPad, "DeviceFamily - .iPad is failing")
     }
     
+    func testInvalidDeviceFamily() {
+        let deviceFamily = DeviceFamily(rawValue: "Apple II")
+        XCTAssert(deviceFamily == .unknown, "DeviceFamily - .unknown is failing")
+    }
+    
     func testDeviceIsSimulator() {
         let deviceFamily = DeviceFamily(rawValue: "iPhone")
         #if arch(i386) || arch(x86_64)
diff --git a/Tests/DeviceModelTests.swift b/Tests/DeviceModelTests.swift
index 21aae2d..0abe55d 100644
--- a/Tests/DeviceModelTests.swift
+++ b/Tests/DeviceModelTests.swift
@@ -325,6 +325,13 @@ class DeviceModelTests: XCTestCase {
         XCTAssert(deviceModel == .iPodTouchSeventhGen , "DeviceModel - .iPodSeventhGen is failing")
     }
     
+    // MARK: Unknown Device Test
+    
+    func testInvalidDeviceModel() {
+        let deviceModel = DeviceModel(identifier: Identifier("iPhone0,1"))
+        XCTAssert(deviceModel == .unknown, "DeviceModel - .unknown is failing")
+    }
+    
     // MARK: Notch test
     func testHasNotch() {
       let notchModels: [DeviceModel] = [.iPhoneX, .iPhoneXS, .iPhoneXSMax, .iPhoneXR, .iPhone11, .iPhone11Pro, .iPhone11ProMax]