diff --git a/google-cloud-storage/src/main/java/com/google/cloud/storage/UnifiedOpts.java b/google-cloud-storage/src/main/java/com/google/cloud/storage/UnifiedOpts.java
index 77cb1344a3..2dae52b8e4 100644
--- a/google-cloud-storage/src/main/java/com/google/cloud/storage/UnifiedOpts.java
+++ b/google-cloud-storage/src/main/java/com/google/cloud/storage/UnifiedOpts.java
@@ -281,6 +281,10 @@ interface ProjectAsSource<O extends Opt> {
     O asSource();
   }
 
+  interface HasherSelector extends BucketObjectHmacKeyAllOpt {
+    Hasher getHasher();
+  }
+
   /**
    * This class extends off {@link ObjectSourceOpt} and {@link ObjectTargetOpt} in order to satisfy
    * some the shimming constraints of the subclasses of {@link OptionShim}.
@@ -589,7 +593,11 @@ static Headers extraHeaders(ImmutableMap<String, String> extraHeaders) {
     return new Headers(extraHeaders);
   }
 
-  static final class Crc32cMatch implements ObjectTargetOpt {
+  static DefaultHasherSelector defaultHasherSelector() {
+    return DefaultHasherSelector.INSTANCE;
+  }
+
+  static final class Crc32cMatch implements ObjectTargetOpt, HasherSelector {
     private static final long serialVersionUID = 8172282701777561769L;
     private final int val;
 
@@ -630,6 +638,11 @@ public Mapper<BidiWriteObjectRequest.Builder> bidiWriteObject() {
       };
     }
 
+    @Override
+    public Hasher getHasher() {
+      return Hasher.noop();
+    }
+
     @Override
     public int hashCode() {
       return Objects.hash(val);
@@ -1315,7 +1328,7 @@ public Mapper<ListObjectsRequest.Builder> listObjects() {
   }
 
   @Deprecated
-  static final class Md5Match implements ObjectTargetOpt {
+  static final class Md5Match implements ObjectTargetOpt, HasherSelector {
     private static final long serialVersionUID = 5237207911268363887L;
     private final String val;
 
@@ -1358,6 +1371,11 @@ public Mapper<BidiWriteObjectRequest.Builder> bidiWriteObject() {
       };
     }
 
+    @Override
+    public Hasher getHasher() {
+      return Hasher.noop();
+    }
+
     @Override
     public int hashCode() {
       return Objects.hash(val);
@@ -1983,8 +2001,8 @@ public Mapper<ListObjectsRequest.Builder> listObjects() {
     }
   }
 
-  static final class UserProject extends RpcOptVal<String>
-      implements BucketSourceOpt,
+  interface BucketObjectHmacKeyAllOpt
+      extends BucketSourceOpt,
           BucketTargetOpt,
           BucketListOpt,
           ObjectSourceOpt,
@@ -1993,6 +2011,18 @@ static final class UserProject extends RpcOptVal<String>
           HmacKeySourceOpt,
           HmacKeyTargetOpt,
           HmacKeyListOpt {
+    @Override
+    default Mapper<RewriteObjectRequest.Builder> rewriteObject() {
+      return Mapper.identity();
+    }
+
+    @Override
+    default Mapper<MoveObjectRequest.Builder> moveObject() {
+      return Mapper.identity();
+    }
+  }
+
+  static final class UserProject extends RpcOptVal<String> implements BucketObjectHmacKeyAllOpt {
     private static final long serialVersionUID = 3962499996741180460L;
 
     private UserProject(String val) {
@@ -2004,28 +2034,10 @@ public Mapper<GrpcCallContext> getGrpcMetadataMapper() {
       return ctx ->
           ctx.withExtraHeaders(ImmutableMap.of("X-Goog-User-Project", ImmutableList.of(val)));
     }
-
-    @Override
-    public Mapper<RewriteObjectRequest.Builder> rewriteObject() {
-      return Mapper.identity();
-    }
-
-    @Override
-    public Mapper<MoveObjectRequest.Builder> moveObject() {
-      return Mapper.identity();
-    }
   }
 
   static final class Headers extends RpcOptVal<ImmutableMap<String, String>>
-      implements BucketSourceOpt,
-          BucketTargetOpt,
-          BucketListOpt,
-          ObjectSourceOpt,
-          ObjectTargetOpt,
-          ObjectListOpt,
-          HmacKeySourceOpt,
-          HmacKeyTargetOpt,
-          HmacKeyListOpt {
+      implements BucketObjectHmacKeyAllOpt {
 
     /**
      * The set of header names which are blocked from being able to be provided for an instance of
@@ -2181,16 +2193,6 @@ private void copyEntries(
         }
       }
     }
-
-    @Override
-    public Mapper<RewriteObjectRequest.Builder> rewriteObject() {
-      return Mapper.identity();
-    }
-
-    @Override
-    public Mapper<MoveObjectRequest.Builder> moveObject() {
-      return Mapper.identity();
-    }
   }
 
   static final class VersionsFilter extends RpcOptVal<@NonNull Boolean> implements ObjectListOpt {
@@ -2606,6 +2608,17 @@ public String toString() {
     }
   }
 
+  static final class DefaultHasherSelector implements HasherSelector, Opt {
+    private static final DefaultHasherSelector INSTANCE = new DefaultHasherSelector();
+
+    private DefaultHasherSelector() {}
+
+    @Override
+    public Hasher getHasher() {
+      return Hasher.defaultHasher();
+    }
+  }
+
   /**
    * Internal "collection" class to represent a set of {@link Opt}s, and to provide useful
    * transformations to individual mappers or to resolve any extractors providing a new instance
@@ -2702,6 +2715,22 @@ Opts<T> projectAsSource() {
       return Utils.mapBuild(builder);
     }
 
+    @VisibleForTesting
+    HasherSelector getHasherSelector() {
+      HasherSelector search = defaultHasherSelector();
+      Predicate<Opt> p = isInstanceOf(HasherSelector.class);
+      for (T opt : opts) {
+        if (p.test(opt)) {
+          search = (HasherSelector) opt;
+        }
+      }
+      return search;
+    }
+
+    Hasher getHasher() {
+      return getHasherSelector().getHasher();
+    }
+
     Mapper<GrpcCallContext> grpcMetadataMapper() {
       return fuseMappers(GrpcMetadataMapper.class, GrpcMetadataMapper::getGrpcMetadataMapper);
     }
@@ -2754,7 +2783,7 @@ Mapper<ReadObjectRequest.Builder> readObjectRequest() {
       return fuseMappers(ObjectSourceOpt.class, ObjectSourceOpt::readObject);
     }
 
-    public Mapper<BidiReadObjectRequest.Builder> bidiReadObjectRequest() {
+    Mapper<BidiReadObjectRequest.Builder> bidiReadObjectRequest() {
       return fuseMappers(ObjectSourceOpt.class, ObjectSourceOpt::bidiReadObject);
     }
 
diff --git a/google-cloud-storage/src/test/java/com/google/cloud/storage/UnifiedOptsTest.java b/google-cloud-storage/src/test/java/com/google/cloud/storage/UnifiedOptsTest.java
index 73d88580a4..e5a38b4365 100644
--- a/google-cloud-storage/src/test/java/com/google/cloud/storage/UnifiedOptsTest.java
+++ b/google-cloud-storage/src/test/java/com/google/cloud/storage/UnifiedOptsTest.java
@@ -20,6 +20,10 @@
 import static com.google.common.truth.Truth.assertWithMessage;
 import static org.junit.Assert.assertThrows;
 
+import com.google.cloud.storage.UnifiedOpts.Crc32cMatch;
+import com.google.cloud.storage.UnifiedOpts.DefaultHasherSelector;
+import com.google.cloud.storage.UnifiedOpts.HasherSelector;
+import com.google.cloud.storage.UnifiedOpts.Md5Match;
 import com.google.cloud.storage.UnifiedOpts.ObjectSourceOpt;
 import com.google.cloud.storage.UnifiedOpts.ObjectTargetOpt;
 import com.google.cloud.storage.UnifiedOpts.Opt;
@@ -146,6 +150,27 @@ public void validateFactoryMethodEnforceNonNull_storage_updateHmacKeyOption() th
     validateFactoryMethodEnforceNonNull(Storage.UpdateHmacKeyOption.class);
   }
 
+  @Test
+  public void getHasher_selectsLastValue() {
+    DefaultHasherSelector first = UnifiedOpts.defaultHasherSelector();
+    Md5Match second = UnifiedOpts.md5Match("asdf");
+    Crc32cMatch third = UnifiedOpts.crc32cMatch(3);
+    Opts<HasherSelector> hasherOpts = Opts.from(first, second, third);
+
+    HasherSelector actual = hasherOpts.getHasherSelector();
+    assertThat(actual).isSameInstanceAs(third);
+  }
+
+  @Test
+  public void hasher_md5Match_noop() {
+    assertThat(UnifiedOpts.md5Match("xyz").getHasher()).isEqualTo(Hasher.noop());
+  }
+
+  @Test
+  public void hasher_crc32cMatch_noop() {
+    assertThat(UnifiedOpts.crc32cMatch(77).getHasher()).isEqualTo(Hasher.noop());
+  }
+
   @Test
   public void transformTo() {
     SecretKey key =
@@ -172,8 +197,8 @@ public byte[] getEncoded() {
             UnifiedOpts.encryptionKey(key),
             // userProject implements both target and source
             UnifiedOpts.userProject("user-project"),
-            // crc32c is not a source opt or a ProjectToSource opt, it should be excluded
-            UnifiedOpts.crc32cMatch(1));
+            // contentType is not a source opt or a ProjectToSource opt, it should be excluded
+            UnifiedOpts.setContentType("application/octet-stream"));
     Opts<ObjectSourceOpt> sourceOpts = targetOpts.transformTo(ObjectSourceOpt.class);
 
     Opts<ObjectSourceOpt> expected =