Jeffrey, this FN Pistol comes in a hard plastic case, owners manual, warranty registration card (2) Magazines (One 12 rd. & One 17 rd), cable lock, bore brush and two interchangeable palmswell grip inserts for optimal hand fit and trigger reach.

yes it comes with 2 backstraps see *****UPC:
845737009236
Description:
FNM FNS-9C 9MM 12/17RD FDE/BLK
Brand:
FN America
Model:
FNS-9C NMS
Type:
Pistol: Semi-Auto
Caliber:
9MM
Finish:
Matte Black
Action:
Double Action
Stock:
FDE Polymer Frame w/ Integral Accessory Rail
Sight:
FT: 1-Dot RR: 2-Dot
Barrel Length:
3.6
Overall Length:
6.7
Weight:
23.4 oz
Capacity:
17+1 & 12+1
# of Mags:
2 (1-12 Round, 1-17 Round)
Receiver:
Flat Dark Earth Polymer
Packaging:
Cable Lock
Features:
Striker Fired, **********Two Interchangeable Backstraps;
Ambidextrous Slide Stop Levers & Magazine Release

Jeffery, yes this should come with the arched backstrap pre-installed and the flat backed one in the box.