diff --git a/PrimerScore.py b/PrimerScore.py
index 04cb912..2215273 100644
--- a/PrimerScore.py
+++ b/PrimerScore.py
@@ -41,6 +41,8 @@
 #                       plateau phase ending, positive reaction calculation threshold,
 #                       and false positive threshold, respectively
 #   set_replicates := Number of replicates. Must be the same for all primer sets.
+#   set_instrument_signal := Maximum fluorescent intensity of instrument. Default is 140000
+#   set_threshold_perc := Threshold percentage of maximum fluorescent intensity of instrument. Default is 0.1
 def initialize(set_weights = [5, 5, 10, 20, 60], set_thresholds = [3000, 200, 0.9, 0.2], set_replicates = 4, set_instrument_signal = 140000, set_threshold_perc = 0.1):
     if not (len(set_weights) == 5):
         raise ValueError('Weights do not contain 5 values. Refer to readme for more information.')