diff --git a/super-gpt.c b/super-gpt.c
index 1a2adce..8b080a0 100644
--- a/super-gpt.c
+++ b/super-gpt.c
@@ -73,6 +73,7 @@ static int load_gpt(struct supertype *st, int fd, char *devname)
 	struct MBR *super;
 	struct GPT *gpt_head;
 	int to_read;
+	unsigned int sector_size;
 
 	free_gpt(st);
 
@@ -81,6 +82,11 @@ static int load_gpt(struct supertype *st, int fd, char *devname)
 		return 1;
 	}
 
+	if (!get_dev_sector_size(fd, devname, &sector_size)) {
+		free(super);
+		return 1;
+	}
+
 	lseek(fd, 0, 0);
 	if (read(fd, super, sizeof(*super)) != sizeof(*super)) {
 	no_read:
@@ -100,6 +106,8 @@ static int load_gpt(struct supertype *st, int fd, char *devname)
 		free(super);
 		return 1;
 	}
+	/* Set offset to second block (GPT header) */
+	lseek(fd, sector_size, SEEK_SET);
 	/* Seem to have GPT, load the header */
 	gpt_head = (struct GPT*)(super+1);
 	if (read(fd, gpt_head, sizeof(*gpt_head)) != sizeof(*gpt_head))
@@ -111,6 +119,8 @@ static int load_gpt(struct supertype *st, int fd, char *devname)
 
 	to_read = __le32_to_cpu(gpt_head->part_cnt) * sizeof(struct GPT_part_entry);
 	to_read =  ((to_read+511)/512) * 512;
+	/* Set offset to third block (GPT entries) */
+	lseek(fd, sector_size*2, SEEK_SET);
 	if (read(fd, gpt_head+1, to_read) != to_read)
 		goto no_read;
 
diff --git a/util.c b/util.c
index 883eaa4..818f839 100644
--- a/util.c
+++ b/util.c
@@ -1378,12 +1378,15 @@ static int get_gpt_last_partition_end(int fd, unsigned long long *endofpart)
 	unsigned long long curr_part_end;
 	unsigned all_partitions, entry_size;
 	unsigned part_nr;
+	unsigned int sector_size = 0;
 
 	*endofpart = 0;
 
 	BUILD_BUG_ON(sizeof(gpt) != 512);
 	/* skip protective MBR */
-	lseek(fd, 512, SEEK_SET);
+	if (!get_dev_sector_size(fd, NULL, &sector_size))
+		return 0;
+	lseek(fd, sector_size, SEEK_SET);
 	/* read GPT header */
 	if (read(fd, &gpt, 512) != 512)
 		return 0;
@@ -1403,6 +1406,8 @@ static int get_gpt_last_partition_end(int fd, unsigned long long *endofpart)
 
 	part = (struct GPT_part_entry *)buf;
 
+	/* set offset to third block (GPT entries) */
+	lseek(fd, sector_size*2, SEEK_SET);
 	for (part_nr = 0; part_nr < all_partitions; part_nr++) {
 		/* read partition entry */
 		if (read(fd, buf, entry_size) != (ssize_t)entry_size)