Checkboxes inside a dynamic table in PHP

I am trying to implement CheckBoxes to each row of a dynamic table. The checkboxes are being displayed correctly but I cannot get it values when I submit.

Here is my code:

 <?php foreach ($arr_devices as $devices) {
                            ?>

                        <tr>

                            <td>

                                <input name="checkbox[]" type="checkbox" id="checkbox[]" value='<? echo $devices["id"]; ?>'>

                            </td>

                            <td>
                                <?php echo '<a href=selectedCustomer.php?device_id=' . urlencode($devices["id"]) . '>' . $devices["id"] . '</a>'; ?>
                            </td>

                            <td>
                                <?php echo '<a href=selectedCustomer.php?device_id=' . urlencode($devices["id"]) . '>' . $devices["serial_imei"] . '</a>'; ?>
                            </td>

                            <td>
                                <?php echo '<a href=selectedCustomer.php?device_id=' . urlencode($devices["id"]) . '>' . $devices["serial_no"] . '</a>'; ?>
                            </td>


                        </tr>
                    <?php } ?>