diff --git a/src/fru_reader.cpp b/src/fru_reader.cpp
index 61d4020..b0ee8fe 100644
--- a/src/fru_reader.cpp
+++ b/src/fru_reader.cpp
@@ -89,3 +89,8 @@
 
     return done;
 }
+
+ssize_t OffsetFRUReader::read(off_t start, size_t len, uint8_t* outbuf)
+{
+    return inner.read(start + offset, len, outbuf);
+}
diff --git a/src/fru_utils.cpp b/src/fru_utils.cpp
index e030ac8..5e8e695 100644
--- a/src/fru_utils.cpp
+++ b/src/fru_utils.cpp
@@ -590,7 +590,7 @@
     return true;
 }
 
-bool findFRUHeader(FRUReader& reader, const std::string& errorHelp,
+bool findFRUHeader(BaseFRUReader& reader, const std::string& errorHelp,
                    std::array<uint8_t, I2C_SMBUS_BLOCK_MAX>& blockData,
                    off_t& baseOffset)
 {
@@ -634,7 +634,7 @@
     return false;
 }
 
-std::vector<uint8_t> readFRUContents(FRUReader& reader,
+std::vector<uint8_t> readFRUContents(BaseFRUReader& reader,
                                      const std::string& errorHelp)
 {
     std::array<uint8_t, I2C_SMBUS_BLOCK_MAX> blockData{};