From WoWWiki

Using the scrolls you may get from  Hermit Ortell, you can create an Object of Beckoning, which allows you to choose which Elemental to summon at a Wind stone in Silithus.

There are various reasons why you would want to decide on which Elemental will appear. For example, as part of your Dungeon Set 2 quest, you will need to summon "The Duke of Cynders", which is a Fire Elemental that can spawn at a medium wind stone, and it might be very time and money consuming to make him spawn if you're unlucky. Another reaon is the immunity of fire elementals to fire and water elementals to water spells.

Objects of Beckoning come in three sizes: Crests (Lesser wind stones), Signets (Medium wind stones) and Scepters (Greater wind stones). They can only be used once.

Summoning the Elemental destroys one associated Object of Beckoning, just like the Twilight trappings are consumed by each summon.

Crest of Beckoning

A Crest of Beckoning can be used at a Lesser wind stone. Creating it requires:

• 1 Scroll: Create Crest of Beckoning (Thottbot links: Earth, Fire, Water, Thunder)
• 1 Rugged Leather

...and one additional reagent, depending on which scroll you have (refer to its tooltip to see which one it is):

• 1 Dense Stone for a Crest of Beckoning: Stone, which will summon: Earthen Templar
• 1 Firebloom for a Crest of Beckoning: Fire, which will summon: Crimson Templar
• 1 Enchanted Water for a Crest of Beckoning: Water, which will summon: Azure Templar
• 1 Elemental Air for a Crest of Beckoning: Thunder, which will summon: Hoary Templar

Signet of Beckoning

A Signet of Beckoning can be used at a medium wind stone. Creating it requires:

• 1 Scroll: Create Signet of Beckoning (Thottbot links: Earth, Fire, Water, Thunder)
• 1 Dark Rune

...and additional reagents, depending on which scroll you have (refer to its tooltip to see which one it is):

• 5 Dense Stones for a Signet of Beckoning: Stone, which will summon: The Duke of Shards
• 5 Firebloom for a Signet of Beckoning: Fire, which will summon: The Duke of Cynders
• 5 Enchanted Water for a Signet of Beckoning: Water, which will summon: The Duke of Fathoms
• 5 Elemental Air for a Signet of Beckoning: Thunder, which will summon: The Duke of Zephyrs

Scepter of Beckoning

A Scepter of Beckoning can be used at a greater wind stone. Creating it requires:

• 1 Scroll: Create Scepter of Beckoning (Thottbot links: Stone, Fire, Water, Thunder)
• 1 Truesilver Rod

...and additional reagents, depending on which scroll you have (refer to its tooltip to see which one it is):

• 20 Dense Stones for a Scepter of Beckoning: Stone, which will summon: Baron Kazum
• 20 Firebloom for a Scepter of Beckoning: Fire, which will summon: Prince Skaldrenox
• 20 Enchanted Water for a Scepter of Beckoning: Water, which will summon: Lord Skwol
• 20 Elemental Air for a Scepter of Beckoning: Thunder, which will summon: High Marshal Whirlaxis