diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 23922dc..db1dbfc 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -13,7 +13,7 @@ jobs:
       matrix:
         ruby:
           - "3.4"
-          - "4.0"
+          - "4.0.6"
 
     steps:
     - uses: actions/checkout@v4
@@ -35,7 +35,7 @@ jobs:
     - name: Set up Ruby
       uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 4.0
+        ruby-version: 4.0.6
         bundler-cache: true
     - name: Set up Chrome
       uses: browser-actions/setup-chrome@v1
diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000..d13e837
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+4.0.6
diff --git a/lib/yookassa/entity/product.rb b/lib/yookassa/entity/product.rb
index 6c55923..b319cc5 100644
--- a/lib/yookassa/entity/product.rb
+++ b/lib/yookassa/entity/product.rb
@@ -62,7 +62,7 @@ module Yookassa
 
       # Amount of excise tax on products including kopeks. Decimal number with 2 digits after the period.
       # Online sales register that support this parameter: Orange Data, Kit Invest.
-      attribute? :excise
+      attribute? :excise, Types::Coercible::Float
 
       # Information about the supplier of product or service. You can specify this parameter if you send the data
       # for creating the receipt using the Receipt after payment scenario.
diff --git a/spec/yookassa/entity/product_spec.rb b/spec/yookassa/entity/product_spec.rb
new file mode 100644
index 0000000..4648174
--- /dev/null
+++ b/spec/yookassa/entity/product_spec.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+RSpec.describe Yookassa::Entity::Product do
+  let(:attributes) do
+    {
+      description: "Fuel",
+      quantity: 1,
+      amount: { value: 100, currency: "RUB" },
+      vat_code: 1
+    }
+  end
+
+  it "defines excise as an optional numeric attribute" do
+    expect(described_class.new(**attributes, excise: "12.34").excise).to eq(12.34)
+    expect(described_class.new(**attributes).excise).to be_nil
+  end
+end