Kunai

Crafted from a single piece of iron, a kunai has a leaf-shaped blade and a ring for a pommel. Adapted from the common trowel, the kunai has a thick blade that is sharpened only near the tip.

Benefit(s) Unlike finer weapons, the kunai can readily substitute for a crowbar or piton without being damaged in the process.

Regarding the description.

Normal iron and cold iron is not the same don't think to much on it.

Range increment

Range increment is how far this weapon can be fired at the penalty shown is to hit without far shot feat and with far shot feat

Range	Without far shot	With far shot feat
10 ft.	0	0
20 ft.	-2	-1
30 ft.	-4	-2
40 ft.	-6	-3
50 ft.	-8	-4

Enhancements

Material Enhancements
Material	Average	Masterwork 1	Hardness	Hit Points	Special
Steel	2 gp	302 gp	10	2
Adamantine		3,002 gp	20	2	Bypass hardness less than 20
Iron, Cold	4 gp	304 gp	10	2	Magical enchantments cost an additional 2,000 gp
Mithral		1,002 gp	15	2	1/2 weight
Silver, Alchemical	22 gp	322 gp	8	1	−1 damage
1Masterwork weapons have a +1 enhancement bonus on attack rolls.

Weapon Enhancements
Bonus Value	Additional Cost 1	Hardness Increase 2	Additional HP 2
+1	+2,000 gp	+2	+10
+2	+8,000 gp	+4	+20
+3	+18,000 gp	+6	+30
+4	+32,000 gp	+8	+40
+5	+50,000 gp	+10	+50
+6*	+72,000 gp 3	+12	+60
+7*	+98,000 gp 3	+14	+70
+8*	+128,000 gp 3	+16	+80
+9*	+162,000 gp 3	+18	+90
+10*	+200,000 gp 3	+20	+100
1 Increase total cost for magical enhancement by 2,000 gp for cold iron weapons. 2 Unlike the additional cost, the increase the weapon's hardness and hit points are only gained from its enhancement bonus, not its special abilities 3 If the weapon has a magical bonus greater than +5 or a special ability worth more than +5, the weapon is epic. Multiply magic cost by 10.