diff --git a/constants_inf.pyx b/constants_inf.pyx
index 5c21258..2743a91 100644
--- a/constants_inf.pyx
+++ b/constants_inf.pyx
@@ -14,7 +14,7 @@ cdef str MODELS_FOLDER = "models"
 cdef int SMALL_SIZE_KB = 3
 
 cdef str SPLIT_SUFFIX = "!split!"
-cdef double TILE_DUPLICATE_CONFIDENCE_THRESHOLD = 0.01
+cdef double TILE_DUPLICATE_CONFIDENCE_THRESHOLD = <double>0.01
 cdef int METERS_IN_TILE = 25
 
 cdef class AnnotationClass: