diff --git a/recipes-wolfssl/wolfssl/commercial/fips-details/wolfssl_%.bbappend b/recipes-wolfssl/wolfssl/commercial/fips-details/wolfssl_%.bbappend
index 17de661..7f0c132 100644
--- a/recipes-wolfssl/wolfssl/commercial/fips-details/wolfssl_%.bbappend
+++ b/recipes-wolfssl/wolfssl/commercial/fips-details/wolfssl_%.bbappend
@@ -1,13 +1,13 @@
 #Adjust these as needed
-WOLFSSL_VERSION=""
+WOLFSSL_VERSION ?= ""
 
 WOLF_LICENSE="WolfSSL_LicenseAgmt_JAN-2022.pdf"
 WOLF_LICENSE_MD5="be28609dc681e98236c52428fadf04dd"
-WOLF_SRC=""
-WOLF_SRC_SHA=""
-WOLF_SRC_PASS=""
+WOLF_SRC ?= ""
+WOLF_SRC_SHA ?= ""
+WOLF_SRC_PASS ?= ""
 
-FIPS_HASH="FFBB0434EB0EF2860CBAF6CB29F8F39B4432439EFD2A24C7D6442CBA8E06A4CC"
+FIPS_HASH ?= "FFBB0434EB0EF2860CBAF6CB29F8F39B4432439EFD2A24C7D6442CBA8E06A4CC"
 
 #Do not adjust these variables
 PR = "commercial.fips"