diff --git a/util/uf2conv.py b/util/uf2conv.py
index 67cf92f169..c658081e29 100755
--- a/util/uf2conv.py
+++ b/util/uf2conv.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python3
-# yapf: disable
 import sys
 import struct
 import subprocess
@@ -151,15 +150,10 @@ class Block:
         flags = 0x0
         if familyid:
             flags |= 0x2000
-        if devicetype:
-            flags |= 0x8000
         hd = struct.pack("<IIIIIIII",
             UF2_MAGIC_START0, UF2_MAGIC_START1,
             flags, self.addr, 256, blockno, numblocks, familyid)
         hd += self.bytes[0:256]
-        if devicetype:
-            hd += bytearray(b'\x08\x29\xa7\xc8')
-            hd += bytearray(devicetype.to_bytes(4, 'little'))
         while len(hd) < 512 - 4:
             hd += b"\x00"
         hd += struct.pack("<I", UF2_MAGIC_END)
@@ -287,8 +281,6 @@ def main():
     parser.add_argument('-f', '--family', dest='family', type=str,
                         default="0x0",
                         help='specify familyID - number or name (default: 0x0)')
-    parser.add_argument('-t' , '--device-type', dest='devicetype', type=str,
-                        help='specify deviceTypeID extension tag - number')
     parser.add_argument('-o', '--output', metavar="FILE", dest='output', type=str,
                         help='write output to named file; defaults to "flash.uf2" or "flash.bin" where sensible')
     parser.add_argument('-d', '--device', dest="device_path",
@@ -318,9 +310,6 @@ def main():
         except ValueError:
             error("Family ID needs to be a number or one of: " + ", ".join(families.keys()))
 
-    global devicetype
-    devicetype = int(args.devicetype, 0) if args.devicetype else None
-
     if args.list:
         list_drives()
     else: