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Backup Guide

How To Wear Your BackStory:
 
    
Sister Sizing
   
WHAT IS SISTER SIZING?

Your current bra size has “Sister Sizes” - alternate sizes where the cup volume stays the same even though the band size and cup letter changes.

FIND YOUR SISTER SIZE:

"Should I wear my Sister Size?":

Do your cups fit smoothly without gaps or spilling?

If your answer is “no,” your bra cups aren’t fitting you the way they should.
  
If your answer is “yes,” see the next question below.

Which hook setting do you use to fasten your bra?

If your answer is “the tightest hook possible,” your Sister Size DOWN just might work for you!

If your answer is “the loosest hook possible,” your Sister Size UP just might work for you!

If your answer is “one in the middle,” either your Sister Size UP or Sister DOWN just might work for you!

30 Band Size
Sister Size DOWN Current Bra Size Sister Size UP
28DD 30D
32C
28DDD 30DD
32D
    
32 Band Size
Sister Size DOWN Current Bra Size Sister Size UP
30D
32C
34B
30DD
32D
34C
30DDD 32DD
34D
    
34 Band Size
Sister Size DOWN Current Bra Size Sister Size UP
32B
34A 36AA
32C
34B
36A
32D
34C
36B
32DD
34D
36C
32DDD 34DD
36D
    
36 Band Size
Sister Size DOWN Current Bra Size Sister Size UP
34B
36A 38AA
34C
36B
38A
34D
36C
38B
34DD
36D
38C
34DDD 36DD
38D
     
38 Band Size
Sister Size DOWN Current Bra Size Sister Size UP
36B
38A 40AA
36C
38B
40A
36D
38C
40B
36DD
38D
40C
    
40 Band Size
Sister Size DOWN Current Bra Size Sister Size UP
38C
40B
42A
38D
40C
42B
    
*Sizes in pink are stocked by BackStory