Good evening to you!! The SAR USA comes with a hard case, manual, cleaning kit, 2 17 round magazines. Yes high capacity SAR USA K12 21 round magazines available at the below link. Hope this helps. Have a good rest of your day.
🇺🇸🇺🇸 'Merica' 🇺🇸🇺🇸
https://sarusa.com/product-tag/k12magazine/

The SAR USA K12 model comes in a SAR branded hard plastic case & includes
(1) owner's manual
(1)warranty registration card
(2) 17rd Magazines
(1)cable lock
(1) bore brush
(1) orange plastic chamber blocker
(1)SAR Sticker
You can purchase extra 17rd and 21rd magazines below:
https://sarusa.com/product/k-12-sport-magazine-17-round/

Hi Teresa and welcome back to the community. The SAR USA K12 model comes in a SAR branded hard plastic case with owner's manual, warranty registration card, (2) 17rd Magazines, cable lock, bore brush, orange plastic chamber blocker and SAR Sticker / Decal. Spare 17rd and 21rd magazines available here; https://sarusa.com/product/k-12-sport-magazine-17-round/ --- Cheers, stay safe and enjoy!

Hi teresa, the K-12 comes in a hard blue carry case, (2) 17rd magazines, cable lock, bore brush, & Sarsilmaz sticker.
21Rd mags are available, out of stock at Bud's budsgunshop.com/product_info.php/products_id/730003177/sar+usa+b6+9mm+21rd+magazine ,
Available from Sarsilmaz here >>> https://sarusa.com/product/p8l-p8s-2000-k12-21-round/
Stay safe & have a great day!