@Override
    public Single<byte[]> writeCharacteristic(@NonNull UUID characteristicUuid, @NonNull final byte[] data) {
        return getCharacteristic(characteristicUuid).flatMap(new Function<BluetoothGattCharacteristic, SingleSource<byte[]>>() {
            @Override
            public SingleSource<byte[]> apply(final BluetoothGattCharacteristic characteristic) throws Exception {
                return writeCharacteristic(characteristic, data);
            }
        });
    }
Value used to disable notifications or indicatinos
mockrxandroidble/src/main/java/com/polidea/rxandroidble2/mockrxandroidble/RxBleConnectionMock.java