diff --git a/dfu/src/main/java/no/nordicsemi/android/dfu/DfuBaseService.java b/dfu/src/main/java/no/nordicsemi/android/dfu/DfuBaseService.java
index 427996c..0ab16ab 100644
--- a/dfu/src/main/java/no/nordicsemi/android/dfu/DfuBaseService.java
+++ b/dfu/src/main/java/no/nordicsemi/android/dfu/DfuBaseService.java
@@ -265,6 +265,11 @@ public abstract class DfuBaseService extends IntentService implements DfuProgres
 	 * It is recommended to use this new service when SDK 13 (or later) is out.
 	 */
 	public static final String EXTRA_UNSAFE_EXPERIMENTAL_BUTTONLESS_DFU = "no.nordicsemi.android.dfu.extra.EXTRA_UNSAFE_EXPERIMENTAL_BUTTONLESS_DFU";
+	/**
+	 * The duration of a delay that will be added before sending each data packet in Secure DFU,
+	 * in milliseconds. This defaults to 0 for backwards compatibility reason.
+	 */
+	public static final String EXTRA_DATA_OBJECT_DELAY = "no.nordicsemi.android.dfu.extra.EXTRA_DATA_OBJECT_DELAY";
 	/**
 	 * This property must contain a boolean value.
 	 * <p>
diff --git a/dfu/src/main/java/no/nordicsemi/android/dfu/DfuServiceInitiator.java b/dfu/src/main/java/no/nordicsemi/android/dfu/DfuServiceInitiator.java
index 5b4ea76..e2694f7 100644
--- a/dfu/src/main/java/no/nordicsemi/android/dfu/DfuServiceInitiator.java
+++ b/dfu/src/main/java/no/nordicsemi/android/dfu/DfuServiceInitiator.java
@@ -82,6 +82,7 @@ public final class DfuServiceInitiator {
 	private boolean disableResume = false;
 	private int numberOfRetries = 0; // 0 to be backwards compatible
 	private int mbrSize = DEFAULT_MBR_SIZE;
+	private long dataObjectDelay = 0; // initially disabled
 
 	private Boolean packetReceiptNotificationsEnabled;
 	private int numberOfPackets = 12;
@@ -183,6 +184,30 @@ public final class DfuServiceInitiator {
 		return this;
 	}
 
+	/**
+	 * This method sets the duration of a delay, that the service will wait before sending each
+	 * data object in Secure DFU. The delay will be done after a data object is created, and before
+	 * any data byte is sent. The default value is 0, which disables this feature.
+	 * <p>
+	 * It has been found, that a delay of at least 300ms reduces the risk of packet lose (the
+	 * bootloader needs some time to prepare flash memory) on DFU bootloader from SDK 15 and 16.
+	 * The delay does not have to be longer than 400 ms, as according to performed tests, such delay
+	 * is sufficient.
+	 * <p>
+	 * The longer the delay, the more time DFU will take to complete (delay will be repeated for
+	 * each data object (4096 bytes)). However, with too small delay a packet lose may occur,
+	 * causing the service to enable PRN and set them to 1 making DFU process very, very slow
+	 * (but reliable).
+	 *
+	 * @param delay the initial delay that the service will wait before sending each data object.
+	 * @since 1.10
+	 * @return the builder
+	 */
+	public DfuServiceInitiator setPrepareDataObjectDelay(final long delay) {
+		this.dataObjectDelay = delay;
+		return this;
+	}
+
 	/**
 	 * Enables or disables the Packet Receipt Notification (PRN) procedure.
 	 * <p>
@@ -759,6 +784,7 @@ public final class DfuServiceInitiator {
 		intent.putExtra(DfuBaseService.EXTRA_DISABLE_RESUME, disableResume);
 		intent.putExtra(DfuBaseService.EXTRA_MAX_DFU_ATTEMPTS, numberOfRetries);
 		intent.putExtra(DfuBaseService.EXTRA_MBR_SIZE, mbrSize);
+		intent.putExtra(DfuBaseService.EXTRA_DATA_OBJECT_DELAY, dataObjectDelay);
 		if (mtu > 0)
 			intent.putExtra(DfuBaseService.EXTRA_MTU, mtu);
 		intent.putExtra(DfuBaseService.EXTRA_CURRENT_MTU, currentMtu);
diff --git a/dfu/src/main/java/no/nordicsemi/android/dfu/SecureDfuImpl.java b/dfu/src/main/java/no/nordicsemi/android/dfu/SecureDfuImpl.java
index e0340d2..da71799 100644
--- a/dfu/src/main/java/no/nordicsemi/android/dfu/SecureDfuImpl.java
+++ b/dfu/src/main/java/no/nordicsemi/android/dfu/SecureDfuImpl.java
@@ -82,6 +82,8 @@ class SecureDfuImpl extends BaseCustomDfuImpl {
 	private BluetoothGattCharacteristic mControlPointCharacteristic;
 	private BluetoothGattCharacteristic mPacketCharacteristic;
 
+	private long prepareObjectDelay;
+
 	private final SecureBluetoothCallback mBluetoothCallback = new SecureBluetoothCallback();
 
 	protected class SecureBluetoothCallback extends BaseCustomBluetoothCallback {
@@ -224,6 +226,8 @@ class SecureDfuImpl extends BaseCustomDfuImpl {
 			requestMtu(requiredMtu);
 		}
 
+		prepareObjectDelay = intent.getLongExtra(DfuBaseService.EXTRA_DATA_OBJECT_DELAY, 0);
+
 		try {
 			// Enable notifications
 			enableCCCD(mControlPointCharacteristic, NOTIFICATIONS);
@@ -580,8 +584,7 @@ class SecureDfuImpl extends BaseCustomDfuImpl {
 			mProgressInfo.setBytesSent(0);
 		}
 
-		final long initialDelay = 400; // ms
-		final long startTime = SystemClock.elapsedRealtime() + initialDelay;
+		final long startTime = SystemClock.elapsedRealtime();
 
 		if (info.offset < mImageSizeInBytes) {
 			int attempt = 1;
@@ -594,10 +597,10 @@ class SecureDfuImpl extends BaseCustomDfuImpl {
 					writeCreateRequest(OBJECT_DATA, availableObjectSizeInBytes);
 					mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION,
                             "Data object (" + (currentChunk + 1) + "/" + chunkCount + ") created");
-					if (currentChunk == 0) {
-						// Waiting until the device is ready to receive first data object.
-						mService.waitFor(initialDelay);
-					}
+					// Waiting until the device is ready to receive the data object.
+					// If prepare data object delay was set in the initiator, the delay will be used
+					// for all data objects.
+					mService.waitFor(prepareObjectDelay > 0 ? prepareObjectDelay : chunkCount == 0 ? 400 : 0);
 					mService.sendLogBroadcast(DfuBaseService.LOG_LEVEL_APPLICATION,
                             "Uploading firmware...");
 				} else {