B King via Amazon has 5000mAh Lisen 0.3" Ultra Slim MagSafe Portable Power Bank (Glacier Gray) on sale for $19.99 - $6 off when you apply promo code W7F2KBG7 at checkout = $13.99. Shipping is free w/ Prime or on orders $35+.

Thanks to Deal Hunter Navy-Wife for sharing this deal.
 
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