diff --git a/furniture-3d-system/scripts/install-product-replacement-rule-sync-timer.sh b/furniture-3d-system/scripts/install-product-replacement-rule-sync-timer.sh
new file mode 100644
index 00000000..8dd549c9
--- /dev/null
+++ b/furniture-3d-system/scripts/install-product-replacement-rule-sync-timer.sh
@@ -0,0 +1,71 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+# Installs the daily sync timer for the JST replacement rules table
+# (rpt.pm_replacementManage -> SupplyChainProductArchiveReplacementRule).
+# The SABC same-product-code merge depends on this table being fresh,
+# so the default schedule runs before the 09:00 SABC tag reconciliation.
+
+BASE="${FURNITURE_PROD_BASE:-/opt/furniture-3d-system-prod}"
+SERVICE_NAME="${PRODUCT_REPLACEMENT_RULE_SYNC_SERVICE_NAME:-furniture-product-replacement-rule-sync}"
+APP_ROOT="$BASE/current/furniture-3d-system"
+SHARED="$BASE/shared"
+APP_ENV="$SHARED/.env"
+SERVICE_FILE="/etc/systemd/system/$SERVICE_NAME.service"
+TIMER_FILE="/etc/systemd/system/$SERVICE_NAME.timer"
+SCHEDULE="${PRODUCT_REPLACEMENT_RULE_SYNC_SCHEDULE:-*-*-* 07:40:00 Asia/Shanghai}"
+RANDOMIZED_DELAY_SEC="${PRODUCT_REPLACEMENT_RULE_SYNC_RANDOMIZED_DELAY_SEC:-5min}"
+
+if [ "$(id -u)" -ne 0 ]; then
+  echo "This installer must run as root." >&2
+  exit 1
+fi
+
+if [ ! -d "$APP_ROOT" ]; then
+  echo "Missing app root: $APP_ROOT" >&2
+  exit 1
+fi
+
+if [ ! -f "$APP_ENV" ]; then
+  echo "Missing app env: $APP_ENV" >&2
+  exit 1
+fi
+
+if command -v systemd-analyze >/dev/null 2>&1; then
+  systemd-analyze calendar "$SCHEDULE" >/dev/null
+fi
+
+cat >"$SERVICE_FILE" <<EOF
+[Unit]
+Description=Sync JST replacement rules into SupplyChainProductArchiveReplacementRule
+After=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=oneshot
+WorkingDirectory=$APP_ROOT
+Environment=NODE_ENV=production
+EnvironmentFile=$APP_ENV
+ExecStart=/bin/bash -lc 'set -euo pipefail; cd "$APP_ROOT"; ./node_modules/.bin/tsx scripts/sync-product-replacement-rules.ts --apply --confirm=sync-product-replacement-rules'
+TimeoutStartSec=1h
+StandardOutput=journal
+StandardError=journal
+EOF
+
+cat >"$TIMER_FILE" <<EOF
+[Unit]
+Description=Sync JST replacement rules once a day
+
+[Timer]
+OnCalendar=$SCHEDULE
+Persistent=true
+RandomizedDelaySec=$RANDOMIZED_DELAY_SEC
+Unit=$SERVICE_NAME.service
+
+[Install]
+WantedBy=timers.target
+EOF
+
+systemctl daemon-reload
+systemctl enable --now "$SERVICE_NAME.timer"
+systemctl list-timers --all "$SERVICE_NAME.timer" --no-pager