The shorter version (the SBS) is actually heavier. It holds more rounds (one more than a standard 4 round magazine) and it's light and shell carrier add weight

The shorter barrel reduces efficiency very little if any, while i adds greatly tot he maneuverability of this home defense shotgun. The side shell carrier (by Mesa Tactical) adds a bit of weight but having spare rounds close at hand are worth their weight in gold when needed. The SBS also has a shorter stock for use with vests and other gear

Here is a step by step breakdown of the features of this Short Barreled Shotgun:

1. a +1 magazine cap that replaces the standard magazine cap and adds another round capacity to the 4 round tubular magazine of the Remington 870

2. a Surefire handgrip / light combo with LED bulb set

3. Mesa Tactical six shell holder

4 Single Point Sling

5 Short (tactical) stock for use with vests and web gear

6. Ghost ring iron sights, Strong and fast to acquire targets

For further comparison here is a third Remington 870 at full (non NFA) length with some home defense add ons. It has the shorter stock, Surefire grip / light and magazine extension. Three great looking and well performing shotguns