Part Number	Location on Vehicle	Spring Capacity	Number of Leaves
43-1555HD	Rear	2,400lbs	4/1

This is an Extra Heavy Duty replacement for the stock three leaf or the four leaf version.

Part Number	Location on Vehicle	Spring Capacity	Number of Leaves
43-1555	Rear	1,900lbs	3/1

Part Number	Location on Vehicle	Spring Capacity	Number of Leaves
43-1679	Rear	1,500lbs	2/1

This is a Standard Duty replacement for the stock three leaf spring.

This part fits the following make/models: 2004 to 2014 - F-150 What's In The Box: 1 Shackle

This part fits the following make/models: 2005 - 2011 F-150 2005 - 2008 Lincoln Mk LT For models with 3" wide rear springs and double centerbolts What's In The Box: 1 Top Cap/Plate

Part Number	Location on Vehicle	Spring Capacity	Number of Leaves
43-1679-2	Rear	N/A	1

This is a Clip Leaf for the standard 43-1679 spring leaf.