diff --git a/py-scripts/lf_wifi_capacity_test.py b/py-scripts/lf_wifi_capacity_test.py
index 13e0f1520..5601d385a 100755
--- a/py-scripts/lf_wifi_capacity_test.py
+++ b/py-scripts/lf_wifi_capacity_test.py
@@ -112,6 +112,8 @@ def __init__(self,
                  graph_groups=None,
                  test_rig="",
                  test_tag="",
+                 payload_size="",
+                 sock_buffer_size="",
                  local_lf_report_dir="",
                  sta_list=None,
                  verbosity="5",
@@ -163,6 +165,8 @@ def __init__(self,
         self.graph_groups = graph_groups
         self.test_rig = test_rig
         self.test_tag = test_tag
+        self.payload_size = payload_size
+        self.sock_buffer_size = sock_buffer_size
         self.local_lf_report_dir = local_lf_report_dir
         self.stations_list = sta_list
         self.verbosity = verbosity
@@ -237,6 +241,10 @@ def run(self):
                 cfg_options.append("test_rig: " + self.test_rig)
             if self.test_tag != "":
                 cfg_options.append("test_tag: " + self.test_tag)
+            if self.payload_size != "":
+                cfg_options.append("pdu_sz: " + self.payload_size)
+            if self.sock_buffer_size != "":
+                cfg_options.append("sock_buffer: " + self.sock_buffer_size)
 
             cfg_options.append("save_csv: 1")
 
@@ -358,6 +366,8 @@ def main():
                         help="Protocol ex.TCP-IPv4")
     parser.add_argument("-d", "--duration", type=str, default="",
                         help="duration in ms. ex. 5000")
+    parser.add_argument("--payload_size", default="", help="Specify payload size for the test")
+    parser.add_argument("--sock_buffer_size", default="", help="Specify socket buffer size for the test")
     parser.add_argument("--verbosity", default="5", help="Specify verbosity of the report values 1 - 11 default 5")
     parser.add_argument("--download_rate", type=str, default="1Gbps",
                         help="Select requested download rate.  Kbps, Mbps, Gbps units supported.  Default is 1Gbps")