diff --git a/stock_packaging_calculator/models/product.py b/stock_packaging_calculator/models/product.py
index 5dd73bac3..68907d2a4 100644
--- a/stock_packaging_calculator/models/product.py
+++ b/stock_packaging_calculator/models/product.py
@@ -8,24 +8,19 @@ from odoo.tools import float_compare
 class Product(models.Model):
     _inherit = "product.product"
 
-    def product_qty_by_packaging(self, prod_qty, min_unit=None):
+    def product_qty_by_packaging(self, prod_qty):
         """Calculate quantity by packaging.
 
+        The minimal quantity is always represented by the UoM of the product.
+
         Limitation: fractional quantities are lost.
 
         :prod_qty: total qty to satisfy.
-        :min_unit: minimal unit of measure as a tuple (qty, name).
-                   Default: to UoM unit.
         :returns: list of tuple in the form [(qty_per_package, package_name)]
-
         """
         packagings = [(x.qty, x.name) for x in self.packaging_ids]
-        if min_unit is None:
-            # You can pass `False` to skip it.
-            single_unit = self.uom_id
-            min_unit = (single_unit.factor, single_unit.name)
-        if min_unit:
-            packagings.append(min_unit)
+        # Add minimal unit
+        packagings.append((self.uom_id.factor, self.uom_id.name))
         return self._product_qty_by_packaging(
             sorted(packagings, reverse=True), prod_qty
         )
@@ -45,7 +40,10 @@ class Product(models.Model):
     def _qty_by_pkg(self, pkg_qty, qty):
         """Calculate qty needed for given package qty."""
         qty_per_pkg = 0
-        while float_compare(qty - pkg_qty, 0.0, precision_digits=3) >= 0.0:
+        while (
+            float_compare(qty - pkg_qty, 0.0, precision_digits=self.uom_id.rounding)
+            >= 0.0
+        ):
             qty -= pkg_qty
             qty_per_pkg += 1
         return qty_per_pkg, qty
diff --git a/stock_packaging_calculator/tests/test_packaging_calc.py b/stock_packaging_calculator/tests/test_packaging_calc.py
index c5836b941..af1c11541 100644
--- a/stock_packaging_calculator/tests/test_packaging_calc.py
+++ b/stock_packaging_calculator/tests/test_packaging_calc.py
@@ -48,19 +48,6 @@ class TestCalc(SavepointCase):
             [(1, "Box"), (30, self.uom_unit.name)],
         )
 
-    def test_calc_4(self):
-        """Test minimal unit override."""
-        self.assertEqual(
-            self.product_a.product_qty_by_packaging(80, min_unit=(5, "Pack 5")),
-            [(1, "Box"), (6, "Pack 5")],
-        )
-
-    def test_calc_5(self):
-        """Test no minimal unit."""
-        self.assertEqual(
-            self.product_a.product_qty_by_packaging(80, min_unit=False), [(1, "Box")]
-        )
-
     def test_calc_6(self):
         """Test fractional qty is lost."""
         self.assertEqual(self.product_a.product_qty_by_packaging(50.5), [(1, "Box")])