1600 × 1600
Source:https://www.walmart.com/ip/Women-Shoes-Point-Toe-Ballet-Flats-For-Women-Flat-Shoes-Slip-On-Shallow-Mouth-Simple-Single-Shoes-Casual-Shoes-Work-Shoes-Black-6-5/1669673823
1000 × 1500
Source:https://people.com/style/best-work-flats/
768 × 768
Source:https://www.walmart.com/ip/TOWED22-Women-Flats-Womens-Flat-Shoes-Classic-Pointed-Toe-Flats-Knit-Dress-Shoes-Soft-Flats-for-Woman-Comfortable-Dressy-Beige/3204972545
488 × 488
Source:https://www.target.com/p/mio-marino-women-s-formal-flat-dress-shoes-beige-size-8/-/A-83896921
636 × 787
Source:https://www.etsy.com/listing/244818328/formal-shoes-for-ladies-evening-shoes
900 × 900
Source:https://www.amazon.com/FRACORA-Breathable-Leather-Loafers-Walking/dp/B08SK8S72C
768 × 768
Source:https://www.walmart.com/ip/TOWED22-Flats-Shoes-Women-Women-s-Pointed-Toe-Ballet-Flat-Elastic-Cross-Strap-Comfortable-Flats-Shoes-Slip-On-Casual-Dress-Shoes-Brown/1084278402
1500 × 1500
Source:https://orthoticshop.com/vionic-desiree-womens-quilted-flat-supportive-dress-shoe.html
488 × 488
Source:https://www.target.com/p/mio-marino-women-s-formal-flat-dress-shoes-black-metallic-size-7-5/-/A-83896944
1080 × 1080
Source:https://www.jonesbootmaker.com/blogs/news/a-guide-to-wearing-flat-shoes