diff --git a/app/services/augmented_part_sync.py b/app/services/augmented_part_sync.py
index 027ac1d..21d42f5 100644
--- a/app/services/augmented_part_sync.py
+++ b/app/services/augmented_part_sync.py
@@ -49,9 +49,19 @@ from app.schemas.augmented_part import AugmentedPartSyncResult
 ATTACHMENT_POINT_NAME = "Occular"
 MM_PER_INCH = 25.4
 
+# e.g.
+#   M8-1.25    - 8mm OD, 1.25 mm pitch
+#   M8 x 1.25
 _ISO_THREAD_RE = re.compile(
-    r"^M\s*(?P<diameter>\d+(?:\.\d+)?)\s*[xX]\s*(?P<pitch>\d+(?:\.\d+)?)$"
+    r"^M\s*(?P<diameter>\d+(?:\.\d+)?)\s*[xX-]\s*(?P<pitch>\d+(?:\.\d+)?)(?P<extra>.*)$"
 )
+
+# e.g.
+#  1.750-32 UNS
+#  1.750-32
+#  1.5625-40
+#
+# Leading digit / period, one or more digits, a dash, then
 _UNC_THREAD_RE = re.compile(
     r"^(?P<diameter>\d+(?:\.\d+)?(?:/\d+)?)\s*-\s*(?P<tpi>\d+)"
     r"\s*(?P<series>UNEF|UNC|UNF|UNS|UN)?$",
@@ -73,15 +83,14 @@ def _parse_float(value: str | None) -> float | None:
 
 def _parse_thread_attribute(value: str) -> tuple[str, dict] | None:
     """Parse a TBXThreadAttribute string as an ISO metric or UNC/UNF thread spec."""
-    m = _ISO_THREAD_RE.match(value)
-    if m:
+    if m := _ISO_THREAD_RE.match(value):
         return "iso", {
             "diameter_mm": float(m.group("diameter")),
             "pitch_mm": float(m.group("pitch")),
+            "extra": float(m.group("extra")),
         }
 
-    m = _UNC_THREAD_RE.match(value)
-    if m:
+    if m := _UNC_THREAD_RE.match(value):
         # Source data often omits the series letters; UNS ("unified special") is the
         # correct designation when the diameter/TPI pairing isn't a standard pitch.
         series = UncSeries((m.group("series") or "UNS").upper())
@@ -126,7 +135,7 @@ async def _add_attachment_point(db: AsyncSession, ap: AugmentedPart, ip: Importe
                 attachment_point_name_id=apn.id,
                 iso_thread_id=thread.id,
             )
-        else:
+        elif kind == "unc":
             depth_in = _parse_float(ip.ProductMaxThreadDepthin)
             thread = await unc_thread_crud.get_by_values(db, depth_in=depth_in, **fields)
             if thread is None:
@@ -224,9 +233,7 @@ async def sync(db: AsyncSession) -> AugmentedPartSyncResult:
     # ------------------------------------------------------------------ phase 1
 
     # IDs referenced in existing associations
-    result = await db.execute(
-        select(augmented_part_imported_parts.c.imported_part_id).distinct()
-    )
+    result = await db.execute(select(augmented_part_imported_parts.c.imported_part_id).distinct())
     all_linked_ids: set[str] = {row[0] for row in result.all()}
 
     # IDs that still exist in imported_parts
@@ -271,9 +278,7 @@ async def sync(db: AsyncSession) -> AugmentedPartSyncResult:
     # ------------------------------------------------------------------ phase 2
 
     # Re-query linked IDs after phase 1 cleanup
-    result = await db.execute(
-        select(augmented_part_imported_parts.c.imported_part_id).distinct()
-    )
+    result = await db.execute(select(augmented_part_imported_parts.c.imported_part_id).distinct())
     now_linked_ids: set[str] = {row[0] for row in result.all()}
     unlinked_ids = current_ids - now_linked_ids