diff --git a/plugins/ebitdo/fu-ebitdo-device.c b/plugins/ebitdo/fu-ebitdo-device.c
index 79ee92729..385c2618f 100644
--- a/plugins/ebitdo/fu-ebitdo-device.c
+++ b/plugins/ebitdo/fu-ebitdo-device.c
@@ -416,10 +416,14 @@ fu_ebitdo_device_write_firmware (FuDevice *device,
 	}
 
 	/* get header and payload */
-	fw_hdr = fu_firmware_get_image_by_id_bytes (firmware, "header", error);
+	fw_hdr = fu_firmware_get_image_by_id_bytes (firmware,
+						    FU_FIRMWARE_IMAGE_ID_HEADER,
+						    error);
 	if (fw_hdr == NULL)
 		return FALSE;
-	fw_payload = fu_firmware_get_image_by_id_bytes (firmware, "payload", error);
+	fw_payload = fu_firmware_get_image_by_id_bytes (firmware,
+							FU_FIRMWARE_IMAGE_ID_PAYLOAD,
+							error);
 	if (fw_payload == NULL)
 		return FALSE;
 
diff --git a/plugins/ebitdo/fu-ebitdo-firmware.c b/plugins/ebitdo/fu-ebitdo-firmware.c
index f7db942bb..7dbae531e 100644
--- a/plugins/ebitdo/fu-ebitdo-firmware.c
+++ b/plugins/ebitdo/fu-ebitdo-firmware.c
@@ -78,13 +78,13 @@ fu_ebitdo_firmware_parse (FuFirmware *firmware,
 
 	/* add header */
 	fw_hdr = g_bytes_new_from_bytes (fw, 0x0, sizeof(FuEbitdoFirmwareHeader));
-	fu_firmware_image_set_id (img_hdr, "header");
+	fu_firmware_image_set_id (img_hdr, FU_FIRMWARE_IMAGE_ID_HEADER);
 	fu_firmware_image_set_bytes (img_hdr, fw_hdr);
 	fu_firmware_add_image (firmware, img_hdr);
 
 	/* add payload */
 	fw_payload = g_bytes_new_from_bytes (fw, sizeof(FuEbitdoFirmwareHeader), payload_len);
-	fu_firmware_image_set_id (img_payload, "payload");
+	fu_firmware_image_set_id (img_payload, FU_FIRMWARE_IMAGE_ID_PAYLOAD);
 	fu_firmware_image_set_addr (img_payload, GUINT32_FROM_LE(hdr->destination_addr));
 	fu_firmware_image_set_bytes (img_payload, fw_payload);
 	fu_firmware_add_image (firmware, img_payload);
diff --git a/plugins/solokey/fu-solokey-device.c b/plugins/solokey/fu-solokey-device.c
index bca5709cb..15a04852c 100644
--- a/plugins/solokey/fu-solokey-device.c
+++ b/plugins/solokey/fu-solokey-device.c
@@ -470,7 +470,9 @@ fu_solokey_device_write_firmware (FuDevice *device,
 	}
 
 	/* verify the signature and reboot back to runtime */
-	fw_sig = fu_firmware_get_image_by_id_bytes (firmware, "signature", error);
+	fw_sig = fu_firmware_get_image_by_id_bytes (firmware,
+						    FU_FIRMWARE_IMAGE_ID_SIGNATURE,
+						    error);
 	if (fw_sig == NULL)
 		return FALSE;
 	return fu_solokey_device_verify (self, fw_sig, error);
diff --git a/plugins/solokey/fu-solokey-firmware.c b/plugins/solokey/fu-solokey-firmware.c
index 9fc856699..e0ee8b984 100644
--- a/plugins/solokey/fu-solokey-firmware.c
+++ b/plugins/solokey/fu-solokey-firmware.c
@@ -88,7 +88,7 @@ fu_solokey_firmware_parse (FuFirmware *firmware,
 	g_string_append (base64_websafe, "==");
 	fw_sig = _g_base64_decode_to_bytes (base64_websafe->str);
 	fu_firmware_image_set_bytes (img_sig, fw_sig);
-	fu_firmware_image_set_id (img_sig, "signature");
+	fu_firmware_image_set_id (img_sig, FU_FIRMWARE_IMAGE_ID_SIGNATURE);
 	fu_firmware_add_image (firmware, img_sig);
 	return TRUE;
 }
diff --git a/src/fu-firmware-image.h b/src/fu-firmware-image.h
index d955c18f1..7c946e6e8 100644
--- a/src/fu-firmware-image.h
+++ b/src/fu-firmware-image.h
@@ -28,6 +28,10 @@ struct _FuFirmwareImageClass
 	gpointer		 padding[28];
 };
 
+#define FU_FIRMWARE_IMAGE_ID_PAYLOAD		"payload"
+#define FU_FIRMWARE_IMAGE_ID_SIGNATURE		"signature"
+#define FU_FIRMWARE_IMAGE_ID_HEADER		"header"
+
 FuFirmwareImage	*fu_firmware_image_new		(GBytes			*bytes);
 gchar		*fu_firmware_image_to_string	(FuFirmwareImage	*self);
 
diff --git a/src/fu-ihex-firmware.c b/src/fu-ihex-firmware.c
index 989623701..b60c9ec10 100644
--- a/src/fu-ihex-firmware.c
+++ b/src/fu-ihex-firmware.c
@@ -268,7 +268,7 @@ fu_ihex_firmware_parse (FuFirmware *firmware,
 	if (buf_signature->len > 0) {
 		g_autoptr(GBytes) data_sig = g_bytes_new (buf_signature->data, buf_signature->len);
 		g_autoptr(FuFirmwareImage) img_sig = fu_firmware_image_new (data_sig);
-		fu_firmware_image_set_id (img_sig, "signature");
+		fu_firmware_image_set_id (img_sig, FU_FIRMWARE_IMAGE_ID_SIGNATURE);
 		fu_firmware_add_image (firmware, img_sig);
 	}
 	return TRUE;
@@ -313,7 +313,8 @@ dfu_firmware_to_ihex_image (FuFirmwareImage *img, GString *str, GError **error)
 		return FALSE;
 
 	/* special case */
-	if (g_strcmp0 (fu_firmware_image_get_id (img), "signature") == 0)
+	if (g_strcmp0 (fu_firmware_image_get_id (img),
+		       FU_FIRMWARE_IMAGE_ID_SIGNATURE) == 0)
 		record_type = DFU_INHX32_RECORD_TYPE_SIGNATURE;
 
 	/* get number of chunks */
diff --git a/src/fu-self-test.c b/src/fu-self-test.c
index ea53d56a0..0079017a7 100644
--- a/src/fu-self-test.c
+++ b/src/fu-self-test.c
@@ -3816,7 +3816,9 @@ fu_firmware_ihex_signed_func (void)
 	g_assert_cmpint (g_bytes_get_size (data_fw), ==, 136);
 
 	/* get the signed image */
-	data_sig = fu_firmware_get_image_by_id_bytes (firmware, "signature", &error);
+	data_sig = fu_firmware_get_image_by_id_bytes (firmware,
+						      FU_FIRMWARE_IMAGE_ID_SIGNATURE,
+						      &error);
 	g_assert_no_error (error);
 	g_assert_nonnull (data_sig);
 	data = g_bytes_get_data (data_sig, &len);