diff --git a/sbol_utilities/sbol3_sbol2_conversion.py b/sbol_utilities/sbol3_sbol2_conversion.py
index d93b1094..d21172ff 100644
--- a/sbol_utilities/sbol3_sbol2_conversion.py
+++ b/sbol_utilities/sbol3_sbol2_conversion.py
@@ -5,7 +5,7 @@
 
 
 # Namespaces
-from rdflib import URIRef
+from rdflib import URIRef, Literal
 
 BACKPORT_NAMESPACE = 'http://sboltools.org/backport#'
 BACKPORT2_VERSION = f'{BACKPORT_NAMESPACE}sbol2version'
@@ -150,8 +150,26 @@ def visit_association(self, a: sbol3.Association):
         raise NotImplementedError('Conversion of Association from SBOL3 to SBOL2 not yet implemented')
 
     def visit_attachment(self, a: sbol3.Attachment):
-        # Priority: 2
-        raise NotImplementedError('Conversion of Attachment from SBOL3 to SBOL2 not yet implemented')
+        att2 = sbol2.Attachment(self._sbol2_identity(a), source=a.source, version=self._sbol2_version(a))
+        self.doc2.addAttachment(att2)
+        
+        if a.hash:
+            # Check if it's SHA1 (SBOL2 only supports SHA1)
+            hash_algorithm = a.hash_algorithm
+            
+            if hash_algorithm.replace("-", "").replace(" ", "").lower() == 'sha1':
+                # It's SHA1, so we can set it directly in SBOL2
+                att2.hash = a.hash
+            else:
+                # It's not SHA1, add as backport extension properties
+                att2.properties[BACKPORT_NAMESPACE + 'hash'] = [Literal(a.hash)]
+                att2.properties[BACKPORT_NAMESPACE + 'hashAlgorithm'] = [Literal(hash_algorithm)]
+        
+        att2.format = str(a.format)
+        att2.size = a.size
+            
+        self._convert_toplevel(a, att2)
+
 
     def visit_binary_prefix(self, a: sbol3.BinaryPrefix):
         # Priority: 4
@@ -456,8 +474,21 @@ def visit_association(self, a: sbol2.Association):
         raise NotImplementedError('Conversion of Association from SBOL2 to SBOL3 not yet implemented')
 
     def visit_attachment(self, a: sbol2.Attachment):
-        # Priority: 2
-        raise NotImplementedError('Conversion of Attachment from SBOL2 to SBOL3 not yet implemented')
+        att3 = sbol3.Attachment(self._sbol3_identity(a), namespace=self._sbol3_namespace(a), source=a.source)
+        self.doc3.add(att3)
+        
+        # Check for backported hash properties first (higher priority)
+        if BACKPORT_NAMESPACE + 'hash' in a.properties:
+            att3.hash = a.properties[BACKPORT_NAMESPACE + 'hash'][0]
+            att3.hash_algorithm = a.properties[BACKPORT_NAMESPACE + 'hashAlgorithm'][0]
+        elif a.hash:
+            att3.hash = a.hash
+            att3.hash_algorithm = 'sha1'
+        
+        att3.format = str(a.format)
+        att3.size = a.size
+            
+        self._convert_toplevel(a, att3)
 
     def visit_collection(self, coll2: sbol2.Collection):
         # Make the Collection object and add it to the document
@@ -632,7 +663,7 @@ def visit_range(self, r2: sbol2.Range):
             cdef = r2.parent.parent
             ns = self._sbol3_namespace(cdef)
             seq_stub = sbol3.Sequence(f'{ns}/{cdef.displayId}Seq/', namespace=ns)
-            cdef.sequence = seq_stup
+            cdef.sequence = seq_stub
             cdef.doc.add(seq_stub)
         r3 = sbol3.Range(seq_ref, r2.start, r2.end)
         self._convert_identified(r2, r3)