Smart Track Rudder systems are known for their rudder that stands vertically when not deployed. This is common option on many newer types of sea kayaks both manufactured overseas (Tiderace, Epic - 18X sea kayak, V5 & V7 PE as an add-on) and in Australia (Audax, Nadgee post-2019).
The blade contains a spring which puts the blade in the water. To retract you need to pull up against the spring and cleat it to keep it up.
If you do not want a rudder blade that stands vertically when not deployed we recommend the Smart track Hybrid Foil system or Kajak Sport Navigator.

They can also be retrofitted to kayaks with the same style of pin or, if there is a vertical stern area, a rear mounting bracket.

Smart Track rudder housings come with the required fixings, pin or bracket, pull cords and instructions in a kit. There is a choice of Standard Foil Blade size (short, single of tandem) which is ordered separately. Most of the housings (except Flow) are metal and the Standard Foil Blades are plastic.

Many of the pin/mounting options are stocked, but not every combination of pin and housing is created.

X = Combination is available
Stocked = normally in stock

The tiller is the plate between the pin and the blade - being extended allows a greater distance of the rudder off the rear of the kayak.

As an alternative to a Rear Mount, it is possible to use a Smart Track Long Pin Housing through a Sea-Lect Design mount (gudgeon).

Pin Sizes:

What you need for a full Smart Track rudder system (new build):

• Smart Track Rudder housing (see table above) with pin or rear mount bracket to suit the stern of your kayak. Kit comes with deck hardware, pull cord, joiners to attach cable to housing.
• Smart Track Foil blade - Short (some surf skis), Single (usually single sea kayaks), Tandem (large /double sea kayaks)
• Footbraces - choice of
• Smart Track Toe Pilot - with either 15' SS cable or barrel locators if using spectra
• Sea-Lect Designs rudder control footbraces (plus either SS cable or 2mm Spectra)
• Kajak Sport Flex-Joint Foot braces or Footrest 2 with Steering
• Cable Housing Kit - if using SS Cable use Smart Track cable control kit. 2mm Spectra is too wide for the inner diameter of this tube so you will need to use instead Nylon Flexible Tube (per metre) plus a set of 6mm tube clamps
• Optional:
• Vertical Adjustment - adjusts height / angle of Smart Track foot braces 
• Bayonet pin sleeve - for securing Bayonet pin housings in a hole at the stern. For plastic kayaks use one with a Flange so it can be screwed in
• Stud mounts for the footbraces - if you don't want to bolt through the hull of your kayak. Both the Smart Track and Sea-Lect Designs stud mount kits (4 stud mounts) fit the Smart track Transitional Footbraces/ Toe Pilots. Note that stud mounts cannot be used with Smart Track Performance Footbraces/ Toe Pilots and the screw access is covered.
• If you have chosen Sealect Design Rudder Control Footbraces you might choose to add a Cable Adjustment kit. (Smart Track Toe-Pilot Fottbraces have a fine adjustment included)