diff --git a/tools/class-v5/harness-box.sh b/tools/class-v5/harness-box.sh
index e4bfbf26d..3a6333539 100755
--- a/tools/class-v5/harness-box.sh
+++ b/tools/class-v5/harness-box.sh
@@ -10,7 +10,7 @@ mkdir -p "$REMOTE_LOG"
 cd "$REMOTE_ROOT"
 IGNEUM_V5_BASE="$BASE" IGNEUM_V5_TMP="/tmp/igneum-fast-time-v5s-$CASE" \
 IGNEUM_V5_BIN="${IGNEUM_V5_BIN:-$REMOTE_ROOT/vendor/igneum-node-class-v5/target/release}" \
-IGNEUM_POW="$REMOTE_ROOT/igneum-pow/target/release/igneum-pow" \
+IGNEUM_POW="${IGNEUM_POW_BIN:-$REMOTE_ROOT/igneum-pow/target/release/igneum-pow}" \
   node infra/fast-time/class-v5-signal.mjs "$@" > "$REMOTE_LOG/$CASE.log" 2>&1
 rc=$?
 cp "/tmp/igneum-fast-time-v5s-$CASE/summary.json" "$REMOTE_LOG/$CASE.json" 2>/dev/null || true
diff --git a/tools/class-v5/harness-remote.sh b/tools/class-v5/harness-remote.sh
index f8daccec0..82e1e3a42 100755
--- a/tools/class-v5/harness-remote.sh
+++ b/tools/class-v5/harness-remote.sh
@@ -30,6 +30,7 @@ rsync -a -e "ssh -i $KEY" "$ROOT/infra/fast-time/class-v5-signal.mjs" "$ROOT/inf
 rsync -a -e "ssh -i $KEY" "$ROOT/tools/class-v5/harness-box.sh" "$HOST:$REMOTE_ROOT/tools/class-v5/"
 # the box side is a script run by path (tools/class-v5/harness-box.sh), not an ssh command string
 # FORK_BIN=<dir on the box> points the harness at another fork build (the node lane's pair build for a fix not yet on class-v5-node)
-ssh -i "$KEY" "$HOST" "IGNEUM_V5_BIN=${FORK_BIN:-} $REMOTE_ROOT/tools/class-v5/harness-box.sh" "$REMOTE_ROOT" "$REMOTE_LOG" "$CASE" "$BASE" $ARGS || true
+# POW_BIN=<igneum-pow binary on the box> points the harness's CLI id read at another crate build (the freeze CLI for a pairing read-back)
+ssh -i "$KEY" "$HOST" "IGNEUM_V5_BIN=${FORK_BIN:-} IGNEUM_POW_BIN=${POW_BIN:-} $REMOTE_ROOT/tools/class-v5/harness-box.sh" "$REMOTE_ROOT" "$REMOTE_LOG" "$CASE" "$BASE" $ARGS || true
 rsync -a -e "ssh -i $KEY" "$HOST:$REMOTE_LOG/$CASE.log" "$HOST:$REMOTE_LOG/$CASE.json" "$OUT/" 2>/dev/null || true
 grep -E "SUMMARY|FAILED CHECK|PROGRAM ID|CLASS SWITCH" "$OUT/$CASE.log" || tail -20 "$OUT/$CASE.log"