diff --git a/gfd/__init__.py b/gfd/__init__.py
index a533607..0e0b578 100644
--- a/gfd/__init__.py
+++ b/gfd/__init__.py
@@ -1,23 +1,108 @@
 from PySide6 import QtWidgets, QtCore
 import gfd.i18n as i18n
+from gfd import sfd
+
 
 class GFDWidget(QtWidgets.QWidget):
     def __init__(self, tr):
         super().__init__()
         self.tr = tr
         self.setWindowTitle(self.tr("window_title"))
-        self.resize(300, 100)
+        self.resize(400, 220)
+
+        self.label = QtWidgets.QLabel(
+            self.tr("hello_world"),
+            alignment=QtCore.Qt.AlignmentFlag.AlignCenter,
+        )
+
+        self.combo = QtWidgets.QComboBox()
+        self.combo.addItem(self.tr("loading_installers") + "…")
+
+        self.refresh_btn = QtWidgets.QPushButton("⟳ " + self.tr("refresh"))
+        self.refresh_btn.clicked.connect(self.reload_installers)
+
+        combo_layout = QtWidgets.QHBoxLayout()
+        combo_layout.addWidget(self.combo)
+        combo_layout.addWidget(self.refresh_btn)
+
+        self.md5_label = QtWidgets.QLabel(
+            "", alignment=QtCore.Qt.AlignmentFlag.AlignCenter
+        )
+
+        layout = QtWidgets.QVBoxLayout(self)
+        layout.addWidget(self.label)
+        layout.addLayout(combo_layout)
+        layout.addWidget(self.md5_label)
+
+        self.combo.currentIndexChanged.connect(self.on_selection_changed)
+
+        QtCore.QTimer.singleShot(0, self.load_installers_async)
+
+    def reload_installers(self):
+        """Triggered by the refresh button."""
+        self.refresh_btn.setEnabled(False)
+        self.combo.clear()
+        self.combo.addItem(self.tr("loading_installers") + "…")
+        self.load_installers_async()
+
+    def load_installers_async(self):
+        """Fetch installer options without freezing the UI."""
+        self.thread = QtCore.QThread()
+        self.worker = SFDWorker()
+        self.worker.moveToThread(self.thread)
+
+        self.thread.started.connect(self.worker.run)
+        self.worker.finished.connect(self.thread.quit)
+        self.worker.finished.connect(self.worker.deleteLater)
+        self.thread.finished.connect(self.thread.deleteLater)
+        self.worker.result_ready.connect(self.populate_installers)
+
+        self.thread.start()
+
+    @QtCore.Slot(list)
+    def populate_installers(self, installers):
+        self.refresh_btn.setEnabled(True)
+        self.combo.clear()
+
+        if not installers:
+            self.combo.addItem(self.tr("no_installers_found"))
+            self.md5_label.setText("")
+            return
+
+        self.installers = installers
+        for item in installers:
+            self.combo.addItem(item["name"], item["md5"])
+
+        self.combo.setCurrentIndex(0)
+        self.on_selection_changed(0)
+
+    @QtCore.Slot(int)
+    def on_selection_changed(self, index):
+        if not hasattr(self, "installers") or not self.installers:
+            return
+        md5 = self.combo.currentData()
+        name = self.combo.currentText()
+        self.md5_label.setText(f"<b>{name}</b><br>MD5: <code>{md5 or 'N/A'}</code>")
+
+
+class SFDWorker(QtCore.QObject):
+    """Background worker to fetch installers safely."""
+
+    finished = QtCore.Signal()
+    result_ready = QtCore.Signal(list)
+
+    @QtCore.Slot()
+    def run(self):
+        data = sfd.fetchInstallerOptions()
+        self.result_ready.emit(data)
+        self.finished.emit()
 
-        label = QtWidgets.QLabel(self.tr("hello_world"), alignment=QtCore.Qt.AlignCenter)
-        lay = QtWidgets.QVBoxLayout(self)
-        lay.addWidget(label)
 
 def run(lang="es"):
     import sys
-    app = QtWidgets.QApplication(sys.argv)
 
+    app = QtWidgets.QApplication(sys.argv)
     tr = i18n.Translator(lang)
     w = GFDWidget(tr)
     w.show()
-
     sys.exit(app.exec())
diff --git a/gfd/i18n/en.py b/gfd/i18n/en.py
index 3017bc8..9ae74e5 100644
--- a/gfd/i18n/en.py
+++ b/gfd/i18n/en.py
@@ -1,4 +1,7 @@
 translations = {
     "hello_world": "Hello, World!",
     "window_title": "Digital Signature Manager",
+    "no_installers_found": "Could not update installer list",
+    "loading_installers": "Loading Installers",
+    "refresh": "Refresh",
 }
diff --git a/gfd/i18n/es.py b/gfd/i18n/es.py
index e57ed7a..20d5330 100644
--- a/gfd/i18n/es.py
+++ b/gfd/i18n/es.py
@@ -1,4 +1,7 @@
 translations = {
     "hello_world": "¡Hola, Mundo!",
     "window_title": "Gestor de Firma Digital",
+    "no_installers_found": "No se pudo actualizar la lista de instaladores",
+    "loading_installers": "Cargando instaladores",
+    "refresh": "Buscar",
 }
diff --git a/gfd/sfd.py b/gfd/sfd.py
new file mode 100644
index 0000000..c082ccb
--- /dev/null
+++ b/gfd/sfd.py
@@ -0,0 +1,68 @@
+import re
+import unicodedata
+import requests
+from bs4 import BeautifulSoup
+
+SFD_URL = "https://soportefirmadigital.com/sfdj/dl.aspx"
+
+
+def _normalize_text(text: str) -> str:
+    """Internal: remove accents, extra spaces, and lowercase."""
+    text = unicodedata.normalize("NFKD", text)
+    text = "".join(c for c in text if not unicodedata.combining(c))
+    return re.sub(r"\s+", " ", text).strip().lower()
+
+
+def fetchInstallerOptions(url: str = SFD_URL):
+    """
+    Fetch the list of installer options from the given Soporte Firma Digital page.
+
+    Args:
+        url (str, optional): Page URL to fetch. Defaults to SFD_URL.
+
+    Returns:
+        list[dict]: Each item is {'name': <str>, 'md5': <str or None>}
+    """
+    try:
+        r = requests.get(url, timeout=8)
+        r.raise_for_status()
+    except requests.RequestException:
+        return []
+
+    soup = BeautifulSoup(r.text, "html.parser")
+
+    installers = [
+        opt.text.strip()
+        for opt in soup.select("#ctl00_certContents_ddlInstaladores option")
+    ]
+    if not installers:
+        return []
+
+    # Extract valid MD5 hashes from embedded JavaScript
+    md5s = {}
+    for name, md5 in re.findall(
+        r"text\s*==\s*'([^']+)'.*?MD5\s*[:=]\s*([A-Za-z0-9]+)",
+        r.text,
+        re.DOTALL,
+    ):
+        md5 = md5.lower()
+        if re.fullmatch(r"[0-9a-f]{32}", md5):  # only valid 32-char hex hashes
+            md5s[_normalize_text(name)] = md5
+
+    results = []
+    for inst in installers:
+        n = _normalize_text(inst)
+        md5 = md5s.get(n)
+        if not md5:
+            for key, val in md5s.items():
+                if key in n or n in key:
+                    md5 = val
+                    break
+        results.append({"name": inst, "md5": md5})
+
+    return results
+
+
+if __name__ == "__main__":
+    for item in fetchInstallerOptions():
+        print(f"{item['name']:<70}  MD5={item['md5'] or 'N/A'}")
diff --git a/requirements.txt b/requirements.txt
index 91c79fa..87cbcfe 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,4 +1,12 @@
+beautifulsoup4==4.14.2
+certifi==2025.10.5
+charset-normalizer==3.4.3
+idna==3.10
 PySide6==6.9.2
 PySide6_Addons==6.9.2
 PySide6_Essentials==6.9.2
+requests==2.32.5
 shiboken6==6.9.2
+soupsieve==2.8
+typing_extensions==4.15.0
+urllib3==2.5.0