+.BR \-b ", " \-\-boundary\-align =\fIalignment\fR
+Specifies the alignment for the FAT and the start of the cluster heap.
+The \fIalignment\fR argument is specified in bytes or may be specified with
+\fBm\fR/\fBM\fR suffix for mebibytes or \fBk\fR/\fBK\fR suffix for kibibytes
+and should be a power of two.
+Some media like SD cards need this for optimal performance and endurance,
+in which case \fIalignment\fR should be set to half of the card's native
+boundary unit size.
+If the card's native boundary unit size is not known, refer to the following
+table of boundary unit sizes recommended by the SD Card Association.
+.\" source: SD Specifications Part 2: File System Specification Version 3.00
+.TS
+center;
+cb1s6cbcb,nnnn.
+Card Capacity Range Cluster Size Boundary Unit
+_
+ \[<=]8 MiB 8 KiB 8 KiB
+>8 MiB \[<=]64 MiB 16 KiB 16 KiB
+>64 MiB \[<=]256 MiB 16 KiB 32 KiB
+>256 MiB \[<=]1 GiB 16 KiB 64 KiB
+>1 GiB \[<=]2 GiB 32 KiB 64 KiB
+>2 GiB \[<=]32 GiB 32 KiB 4 MiB
+>32 GiB \[<=]128 GiB 128 KiB 16 MiB
+>128 GiB \[<=]512 GiB 256 KiB 32 MiB
+>512 GiB \[<=]2 TiB 512 KiB 64 MiB
+.TE
+The default is always 1 MiB.
+.TP
+.BR \-s ", " \-\-sector\-size =\fIsize\fR
+Specifies the sector size of the exFAT file system.
+The \fIsize\fR argument is specified in bytes or may be specified with
+\fBk\fR/\fBK\fR suffix for kibibytes and must either 512, 1024, 2048 or 4096
+bytes.
+The default value is the sector size reported by the device, or 512 bytes if the
+device sector size cannot be determined.