diff --git a/segmentmodel.py b/segmentmodel.py
index 172e21c7278e46daeefd25f4b2518e45bfa83313..c3d044f3504355dd24f376a5eb78e0376bcf0a1c 100644
--- a/segmentmodel.py
+++ b/segmentmodel.py
@@ -823,7 +823,7 @@ class DoubleStrandedSegment(Segment):
             end3 = end3.end3
         self._connect_ends( self.end5, end3, type_, force_connection = force_connection )
 
-    def add_crossover(self, nt, other, other_nt, strands_fwd=(True,False), nt_on_5prime=True):
+    def add_crossover(self, nt, other, other_nt, strands_fwd=(True,False), nt_on_5prime=True, type_="crossover"):
         """ Add a crossover between two helices """
         ## Validate other, nt, other_nt
         ##   TODO
@@ -842,7 +842,7 @@ class DoubleStrandedSegment(Segment):
             # TODOTODO: may need to subtract or add a little depending on 3prime/5prime
             assert(c >= 0 and c <= 1)
             other_loc = other.get_location_at(c, strands_fwd[1])
-            self._connect(other, Connection( loc, other_loc, type_="crossover" ))
+            self._connect(other, Connection( loc, other_loc, type_=type_ ))
             if nt_on_5prime:
                 loc.is_3prime_side_of_connection = False
                 other_loc.is_3prime_side_of_connection = True