iPhone XR Length 5.25" x Width 4.25"
Stretched strap size about 50" dependent on the weight of the phone.
 
Detailed Overview: 
Every bag is 100% handmade by me (hand-knitted with a crochet finish).
Materials: acrylic yarn
 
100% Acrylic
Machine Washable & Dryable
Recommend placing in a laundry net bag to prevent tangling strap with other pieces of laundry. This should insure a long life for your bag. I still use the first bag I made over 10 years ago.
 
Size of bag varies as each individual bag is made and it’s  strap size when stretched will be displayed. Designs take into account possible case coverings and larger pop out holders. A snug fit is most desirable for most of us.
 
Small : IPod Length 4.0" x Width 3.0" 
Medium : My iPhone XR Length 5.5" x Width 4.0”
Large :  Length 7.0" x Width 4.0"
 
NO Lining inside
 
Crossbody typical strap length measurement will vary when stretched and also varies per weight of phone or iPod. To get a better idea of fit you can measure phone and desired entire strap length before you purchase from what's in stock.
 
Typical strap size length recommendations although since each bag is unique, they maybe very slight size variations displayed. 
 
35-38"  (Child)
40-43"  (Young Adult)
45-48" (Adult)
50-53" (Extra Tall Adult)