BELT ACCESSORIES
There are three standard items that are worn on the belt that we'll cover:
1. The O2 cannister (aka thermal detonator) worn on the backs of almost all stormtroopers
2. Comlink (worn by Luke in ANH)
3. Grapling Hook (worn by Luke in ANH)
O2 Cannister

CRL
The CRL states:
* An O2 canister (aka thermal detonator) must be present on the back attached to the belt. This is a gray cylinder 2-2.5 inches in diameter with white end caps with a white control pad affixed, facing outwards. It may be permanently affixed using fasteners or be clipped on.
Note that this is a mandatory item for all stormtroopers, the only exception being the Heavy Weapons Trooper who has the option of not wearing one (as the pack will normally make this impossible).
The O2 cannister can be riveted or velcro'd to the belt, however the way it was done in the movies has proven to be popular. This method involves affixing the cannister to bankers clips and then just clipping the cannister to the belt.
POPULAR MODS
Popular modifications including having the ends be screwed on or connected via a stretchy cord, which allows people to store items in there. Some people also mount lights to the control panel, but this is considered non-canon and should be used at only casual events or cons.
ROTJ Variation
The ROTJ trooper actually uses a slig htly different O2 cannister. Thanks to TK-J for realizing this detail and creating the a good reproduction.

TUTORIAL THREADS
TIP: Thermal Detonator Attachment Help - http://forum.whitearmor.net/index.php?showtopic=9953
SELLERS
Thermal detonators usually come with your armor. From time to time people sell them completed, but they are not sold normally this way.
REFERENCE IMAGES
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COMLINK
This is worn on the front of Luke's belt when he was posing as a stormtrooper and comes in a few variants. Keith created a very accurate one shown below:
It's also easy enough to create a reasonable fascimile with parts from Home Depot as seen here which matches that of the Visual Dictionary
The simplest way to attach it is with a simple spring clip affixed to the belt.
TUTORIAL THREADS
Scratch Built Comlink - http://forum.whitearmor.net/index.php?showtopic=9354
SELLERS
EVO3 - http://forum.whitearmor.net/index.php?showtopic=5332
REFERENCE IMAGES
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GRAPLING HOOK
This is comprised of two parts, the grapling hook itself and the box that holds it on the belt. This is only ever worn by Luke posing as a stormtrooper (and of course, the hapless TK guarding the Falcon's ramp before having his armor taken).
SELLERS
Resin Grapling Hooks by EVO3 - http://forum.whitearmor.net/index.php?showtopic=8449
Machined Grappling Hooks by EVO3 - http://forum.whitearmor.net/index.php?showtopic=8013
Grappling Hook Boxes by vactrooper : http://forum.whitearmor.net/index.php?showtopic=8044
REFERENCE PICTURES
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