diff --git a/apps/chanora_flutter/lib/l10n/app_en.arb b/apps/chanora_flutter/lib/l10n/app_en.arb
index d2b0614..5a15685 100644
--- a/apps/chanora_flutter/lib/l10n/app_en.arb
+++ b/apps/chanora_flutter/lib/l10n/app_en.arb
@@ -40,6 +40,12 @@
       "backend": { "type": "String" }
     }
   },
+  "pttCapabilityBoundKey": "Key: {key}",
+  "@pttCapabilityBoundKey": {
+    "placeholders": {
+      "key": { "type": "String" }
+    }
+  },
   "pttCapabilityExplainTitle": "Push-to-Talk capability",
   "pttCapabilityExplainFocusedHeading": "Focused PTT",
   "pttCapabilityExplainFocusedBody": "Chanora is currently using Focused Push-to-Talk: the binding only fires while the Chanora window is focused. This is the universal fallback used on every platform when a global capture path is not available.",
diff --git a/apps/chanora_flutter/lib/l10n/app_zh.arb b/apps/chanora_flutter/lib/l10n/app_zh.arb
index 7847c6a..bea46a8 100644
--- a/apps/chanora_flutter/lib/l10n/app_zh.arb
+++ b/apps/chanora_flutter/lib/l10n/app_zh.arb
@@ -30,6 +30,7 @@
   "pttTransmitting": "正在发送…",
   "pttHoldToTalkSemanticsHint": "按住进行语音发送，松开停止。",
   "pttCapabilityBadge": "对讲能力：{level}（{backend}）",
+  "pttCapabilityBoundKey": "按键：{key}",
   "pttCapabilityExplainTitle": "对讲能力说明",
   "pttCapabilityExplainFocusedHeading": "聚焦对讲",
   "pttCapabilityExplainFocusedBody": "Chanora 当前使用聚焦对讲：按键只在 Chanora 窗口处于聚焦时生效。这是所有平台在无法启用全局采集时的通用回退方案。",
diff --git a/apps/chanora_flutter/lib/l10n/generated/app_localizations.dart b/apps/chanora_flutter/lib/l10n/generated/app_localizations.dart
index 4abfc6d..02a0c32 100644
--- a/apps/chanora_flutter/lib/l10n/generated/app_localizations.dart
+++ b/apps/chanora_flutter/lib/l10n/generated/app_localizations.dart
@@ -253,6 +253,12 @@ abstract class AppL10n {
   /// **'PTT: {level} ({backend})'**
   String pttCapabilityBadge(String level, String backend);
 
+  /// No description provided for @pttCapabilityBoundKey.
+  ///
+  /// In en, this message translates to:
+  /// **'Key: {key}'**
+  String pttCapabilityBoundKey(String key);
+
   /// No description provided for @pttCapabilityExplainTitle.
   ///
   /// In en, this message translates to:
diff --git a/apps/chanora_flutter/lib/l10n/generated/app_localizations_en.dart b/apps/chanora_flutter/lib/l10n/generated/app_localizations_en.dart
index 06cbc3c..b134b4e 100644
--- a/apps/chanora_flutter/lib/l10n/generated/app_localizations_en.dart
+++ b/apps/chanora_flutter/lib/l10n/generated/app_localizations_en.dart
@@ -96,6 +96,11 @@ class AppL10nEn extends AppL10n {
     return 'PTT: $level ($backend)';
   }
 
+  @override
+  String pttCapabilityBoundKey(String key) {
+    return 'Key: $key';
+  }
+
   @override
   String get pttCapabilityExplainTitle => 'Push-to-Talk capability';
 
diff --git a/apps/chanora_flutter/lib/l10n/generated/app_localizations_zh.dart b/apps/chanora_flutter/lib/l10n/generated/app_localizations_zh.dart
index 03870cb..67db686 100644
--- a/apps/chanora_flutter/lib/l10n/generated/app_localizations_zh.dart
+++ b/apps/chanora_flutter/lib/l10n/generated/app_localizations_zh.dart
@@ -93,6 +93,11 @@ class AppL10nZh extends AppL10n {
     return '对讲能力：$level（$backend）';
   }
 
+  @override
+  String pttCapabilityBoundKey(String key) {
+    return '按键：$key';
+  }
+
   @override
   String get pttCapabilityExplainTitle => '对讲能力说明';
 
diff --git a/apps/chanora_flutter/lib/main.dart b/apps/chanora_flutter/lib/main.dart
index a38102f..87c3f56 100644
--- a/apps/chanora_flutter/lib/main.dart
+++ b/apps/chanora_flutter/lib/main.dart
@@ -115,6 +115,16 @@ class _BetaHomeState extends State<_BetaHome> {
   String _pttLevel = 'L0Focused';
   String _pttBackendId = 'focused';
   String _pttBoundInputClass = 'keyboard';
+  // Last platform-neutral key label the user saved in the
+  // `_PttBindingCaptureDialog` (e.g. "Space", "F10",
+  // "mouse-side-button:8"). Surfaced next to the capability
+  // badge so the user can remember which key drives PTT. The
+  // bridge-side `PttController` (SDD-088) holds the authoritative
+  // binding; this is a display-only cache that resets on app
+  // restart. Per DEC-027 the raw OS key code never lives here —
+  // only the platform-neutral label that already crossed into
+  // the Rust side.
+  String _pttBoundKeyLabel = '';
 
   List<rust.BridgeBookmark> _bookmarks = const [];
 
@@ -435,6 +445,15 @@ class _BetaHomeState extends State<_BetaHome> {
         inputClass: binding.inputClass,
         platformKey: binding.platformKey,
       );
+      // Cache the captured label so the badge can surface "Key:
+      // Space" / "Key: Mouse4" next to the capability descriptor.
+      // The bridge holds the authoritative binding; this is only
+      // for display continuity until the next app restart.
+      if (mounted) {
+        setState(() {
+          _pttBoundKeyLabel = binding.platformKey;
+        });
+      }
     } catch (e) {
       if (!mounted) return;
       // Surface the failure as a snackbar so the user sees that
@@ -723,6 +742,7 @@ class _BetaHomeState extends State<_BetaHome> {
                   pttLevel: _pttLevel,
                   pttBackendId: _pttBackendId,
                   pttBoundInputClass: _pttBoundInputClass,
+                  pttBoundKeyLabel: _pttBoundKeyLabel,
                   onPttDown: () => _setPtt(true),
                   onPttUp: () => _setPtt(false),
                   onToggleInputMute: _toggleInputMute,
@@ -881,6 +901,7 @@ class _AudioControls extends StatefulWidget {
     required this.pttLevel,
     required this.pttBackendId,
     required this.pttBoundInputClass,
+    required this.pttBoundKeyLabel,
     required this.onPttDown,
     required this.onPttUp,
     required this.onToggleInputMute,
@@ -896,6 +917,7 @@ class _AudioControls extends StatefulWidget {
   final String pttLevel;
   final String pttBackendId;
   final String pttBoundInputClass;
+  final String pttBoundKeyLabel;
   final VoidCallback onPttDown;
   final VoidCallback onPttUp;
   final VoidCallback onToggleInputMute;
@@ -935,6 +957,7 @@ class _AudioControlsState extends State<_AudioControls> {
           level: widget.pttLevel,
           backendId: widget.pttBackendId,
           boundInputClass: widget.pttBoundInputClass,
+          boundKeyLabel: widget.pttBoundKeyLabel,
           onConfigure: widget.onConfigurePtt,
         ),
         // Accessibility (SysRS-262 + SysRS-282 + SysRS-263):
@@ -1069,6 +1092,7 @@ class PttCapabilityBadge extends StatelessWidget {
     required this.level,
     required this.backendId,
     required this.boundInputClass,
+    required this.boundKeyLabel,
     required this.onConfigure,
   });
 
@@ -1084,6 +1108,14 @@ class PttCapabilityBadge extends StatelessWidget {
   /// or empty when no binding is set).
   final String boundInputClass;
 
+  /// Platform-neutral key label captured by the binding dialog
+  /// (e.g. `"Space"`, `"F10"`, `"mouse-side-button:8"`). Empty
+  /// when the user has not saved a binding in the current
+  /// process. Display-only; the bridge holds the authoritative
+  /// binding. Per DEC-027 this string is the same one already
+  /// crossed into the Rust side — no new privacy surface.
+  final String boundKeyLabel;
+
   /// Open the configure-binding dialog. Wired by the caller.
   final VoidCallback onConfigure;
 
@@ -1165,38 +1197,59 @@ class PttCapabilityBadge extends StatelessWidget {
         : '$badgeLabel\n($boundInputClass)';
     return Padding(
       padding: const EdgeInsets.only(bottom: 6),
-      child: Tooltip(
-        message: tooltipMessage,
-        child: Row(
-          children: [
-            Icon(
-              _isFocused ? Icons.crop_free : Icons.public,
-              size: 14,
-              color: theme.colorScheme.onSurfaceVariant,
+      child: Column(
+        crossAxisAlignment: CrossAxisAlignment.start,
+        children: [
+          Tooltip(
+            message: tooltipMessage,
+            child: Row(
+              children: [
+                Icon(
+                  _isFocused ? Icons.crop_free : Icons.public,
+                  size: 14,
+                  color: theme.colorScheme.onSurfaceVariant,
+                ),
+                const SizedBox(width: 4),
+                Expanded(
+                  child: Text(
+                    badgeLabel,
+                    style: theme.textTheme.bodySmall?.copyWith(
+                      color: theme.colorScheme.onSurfaceVariant,
+                    ),
+                  ),
+                ),
+                if (_isFocused)
+                  IconButton(
+                    icon: const Icon(Icons.info_outline, size: 16),
+                    tooltip: l10n.pttCapabilityExplainTitle,
+                    visualDensity: VisualDensity.compact,
+                    onPressed: () => _openExplanationSheet(context),
+                  ),
+                TextButton.icon(
+                  icon: const Icon(Icons.tune, size: 14),
+                  label: Text(l10n.pttConfigureAction),
+                  onPressed: onConfigure,
+                ),
+              ],
             ),
-            const SizedBox(width: 4),
-            Expanded(
+          ),
+          // Second line: show which key the user just bound, so
+          // they can remember what to press. Only rendered when a
+          // binding has been saved in the current process (the
+          // bridge holds the authoritative binding across restarts;
+          // this label is display-only).
+          if (boundKeyLabel.isNotEmpty)
+            Padding(
+              padding: const EdgeInsets.only(left: 18, top: 2),
               child: Text(
-                badgeLabel,
+                l10n.pttCapabilityBoundKey(boundKeyLabel),
                 style: theme.textTheme.bodySmall?.copyWith(
                   color: theme.colorScheme.onSurfaceVariant,
+                  fontFamily: 'monospace',
                 ),
               ),
             ),
-            if (_isFocused)
-              IconButton(
-                icon: const Icon(Icons.info_outline, size: 16),
-                tooltip: l10n.pttCapabilityExplainTitle,
-                visualDensity: VisualDensity.compact,
-                onPressed: () => _openExplanationSheet(context),
-              ),
-            TextButton.icon(
-              icon: const Icon(Icons.tune, size: 14),
-              label: Text(l10n.pttConfigureAction),
-              onPressed: onConfigure,
-            ),
-          ],
-        ),
+        ],
       ),
     );
   }