diff --git a/AppleModels/DataBase/MacBook/MB101.yaml b/AppleModels/DataBase/MacBook/MB101.yaml
index c0366bd6..7ad1488a 100644
--- a/AppleModels/DataBase/MacBook/MB101.yaml
+++ b/AppleModels/DataBase/MacBook/MB101.yaml
@@ -262,4 +262,4 @@ AppleModelYear:
   - 2018
   - 2019
 MinimumOSVersion: "10.12.5"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/AppleModels/DataBase/MacBookPro/MBP141.yaml b/AppleModels/DataBase/MacBookPro/MBP141.yaml
index 80fb1668..59b8a318 100644
--- a/AppleModels/DataBase/MacBookPro/MBP141.yaml
+++ b/AppleModels/DataBase/MacBookPro/MBP141.yaml
@@ -155,4 +155,4 @@ AppleModelYear:
   - 2018
   - 2019
 MinimumOSVersion: "10.12.5"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/AppleModels/DataBase/MacBookPro/MBP142.yaml b/AppleModels/DataBase/MacBookPro/MBP142.yaml
index 8c43da30..90c5fa63 100644
--- a/AppleModels/DataBase/MacBookPro/MBP142.yaml
+++ b/AppleModels/DataBase/MacBookPro/MBP142.yaml
@@ -248,4 +248,4 @@ AppleModelYear:
   - 2017
   - 2018
 MinimumOSVersion: "10.12.5"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/AppleModels/DataBase/MacBookPro/MBP143.yaml b/AppleModels/DataBase/MacBookPro/MBP143.yaml
index 3562fe0c..506dcd91 100644
--- a/AppleModels/DataBase/MacBookPro/MBP143.yaml
+++ b/AppleModels/DataBase/MacBookPro/MBP143.yaml
@@ -211,4 +211,4 @@ AppleModelYear:
   - 2017
   - 2018
 MinimumOSVersion: "10.12.5"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/AppleModels/DataBase/iMac/IM181.yaml b/AppleModels/DataBase/iMac/IM181.yaml
index 3b0f9d01..d1ddb27b 100644
--- a/AppleModels/DataBase/iMac/IM181.yaml
+++ b/AppleModels/DataBase/iMac/IM181.yaml
@@ -118,4 +118,4 @@ AppleModelYear:
   - 2020
   - 2021
 MinimumOSVersion: "10.12.4"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/AppleModels/DataBase/iMac/IM182.yaml b/AppleModels/DataBase/iMac/IM182.yaml
index 5e8804fe..2661db2f 100644
--- a/AppleModels/DataBase/iMac/IM182.yaml
+++ b/AppleModels/DataBase/iMac/IM182.yaml
@@ -145,4 +145,4 @@ AppleModelYear:
   - 2018
   - 2019
 MinimumOSVersion: "10.12.4"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/AppleModels/DataBase/iMac/IM183.yaml b/AppleModels/DataBase/iMac/IM183.yaml
index 3b2d2275..3dbc410e 100644
--- a/AppleModels/DataBase/iMac/IM183.yaml
+++ b/AppleModels/DataBase/iMac/IM183.yaml
@@ -153,4 +153,4 @@ AppleModelYear:
   - 2018
   - 2019
 MinimumOSVersion: "10.12.4"
-MaximumOSVersion: null
+MaximumOSVersion: "13.4"
diff --git a/Utilities/macrecovery/boards.json b/Utilities/macrecovery/boards.json
index dff6f88b..489daa31 100644
--- a/Utilities/macrecovery/boards.json
+++ b/Utilities/macrecovery/boards.json
@@ -1,5 +1,5 @@
 {
- "Mac-EE2EBD4B90B839A8": "latest",
+ "Mac-EE2EBD4B90B839A8": "13.4",
  "Mac-BE0E8AC46FE800CC": "11.7.7",
  "Mac-9AE82516C7C6B903": "12.6.6",
  "Mac-942452F5819B1C1B": "10.13.6",
@@ -26,9 +26,9 @@
  "Mac-473D31EABEB93F9B": "12.6.6",
  "Mac-66E35819EE2D0D05": "12.6.6",
  "Mac-A5C67F76ED83108C": "12.6.6",
- "Mac-B4831CEBD52A0C4C": "latest",
- "Mac-CAD6701F7CEA0921": "latest",
- "Mac-551B86E5744E2388": "latest",
+ "Mac-B4831CEBD52A0C4C": "13.4",
+ "Mac-CAD6701F7CEA0921": "13.4",
+ "Mac-551B86E5744E2388": "13.4",
  "Mac-937A206F2EE63C01": "latest",
  "Mac-827FB448E656EC26": "latest",
  "Mac-1E7E29AD0135F9BC": "latest",
@@ -68,9 +68,9 @@
  "Mac-DB15BD556843C820": "12.6.6",
  "Mac-65CE76090165799A": "12.6.6",
  "Mac-B809C3757DA9BB8D": "12.6.6",
- "Mac-4B682C642B45593E": "latest",
- "Mac-77F17D7DA9285301": "latest",
- "Mac-BE088AF8C5EB4FA2": "latest",
+ "Mac-4B682C642B45593E": "13.4",
+ "Mac-77F17D7DA9285301": "13.4",
+ "Mac-BE088AF8C5EB4FA2": "13.4",
  "Mac-AA95B1DDAB278B95": "latest",
  "Mac-63001698E7A34814": "latest",
  "Mac-CFF7D910A743CAAF": "latest",