Ideally 'my' Case needed to provide all round protection with security against being dropped when cold hands are the order of the day, at the same time having the ability to contain the important items normally caried in a Wallet.
I have settled on a Piel Frama Leather Case with a flip over magnetically latching cover.
The 'wallet' section is in the flap which serves as a protector for the screen.
Max capacity is a UK Drivers [Photo Card] Licence, 3 other plastic cards, a couple of folded Bank Notes and a spare Key for my house.
More than the above and it will pop open too easily.
This has enabled me to ditch my old wallet and achieve another step in my iPhone 'gizmo' replacement program.
The end result is a package that is slightly slimmer than the combined iPhone, in a very slim sheath, plus the old wallet.
When carried on the supplied Belt Clip if feels very secure and is out of harms way when I am working.
The only thing missing on the Case was place to attach a Lanyard or Wrist Strap.
This has been resolved by fitting a DIY Attachment which is held in place by the Case Fitting which connects to the Belt Clip.
For those who do not require the use of a Belt Clip, the Case Fitting is completely removable and provided an easy means of securing my 'Attachment', which is free to rotate about the Case Fitting.
This latter feature makes it possible to wear the Belt Clip on either left or right hand side.
The Lanyard is a two part arrangement, the first worn around the neck and the second part [effectively a Wrist Strap] clipped by Carabiners to both the first part and the iPhone.
This set up allows the iPhone to be detached from tethering around the neck and be mounted in the vehicle.
The Wrist Strap is draped over the Vehicle Mount as security against accidental dislodgement.
The Vehicle Mount comprises a Stainless Steel Plate carrying part of a Griffin Window Seat Bracket with the original iPhone Support Plate modified to accept a spare Belt Clip.
The iPhone remains in it's Case when in use as a SAT NAV.
The Belt Clips each have a release button which have to be pressed quite firmly.
They say a Picture paints a .....................

Attachment fitted to Case, it is made from Stainless Steel 0.6mm thick with a brushed finish. The marks on it show that it is protecting the Case from abrasion by the Belt Clip.

Triangular 'ring' protrudes just enough to take the Carabiner, soon as I can lay hands on suitable material this 'ring' will be made from Stainless Steel.

This Lanyard- Wrist Strap set up is designed to avoid the iPhone landing here!
EDIT: Clarified the caption above.