The only saddle pad endorsed by back surgeons, master saddlers and veterinarians.

Saddle Fitting Solutions

What is ThinLine?

ThinLine is a thin, shock absorbing non slip breathable foam.

Where is the ThinLine?

It is sewn onto the panel of our saddle pads. Here you can see the ThinLine foam on top of a western cotton liner pad. 

Saddle Fitting Solutionsendurance round skirt saddle fit pad


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Saddle fitting solutions are easy and with ThinLine saddle pad shim inserts

you will double your results by saddle fitting with the best therapeutic materials.

Saddle Fitting Solutions








  • High Withers: Add Front shims to any pad.
  • Hollow or Sway  Backs: Add bridging shims.
  • Rider Balance: Adding a pair of shims to one side can fix balance issues.
  • Saddle Balance: Front or rear Shims, depending on your issue.
  • Saddle Slippage: Generally no shims are needed, the ThinLine Pad alone will solve this.
  • Saddle Pad Slippage: Generally your tree is too wide. Add a Full Shim.
  • Equine or Rider Back Soreness: No shims needed, ThinLine protects both.
  • Equine Asymmetry: place both of the pair of shims on the hollow side.
  • Kissing Spine Relief: Add a Full Shim to any ThinLine pad.
  • Treeless Saddle Pad Comfort: Add a Full Shim to any ThinLine Pad.

Photo: Front, Bridging and Rear Saddle Fit Shims created from the Full Trim To Fit Shim.

Stacking and layering saddle fitting shims.

  • ThinLine pads accept up to three 1/4 inch saddle fit shims in a single location.
  • 1/4 inch front, bridging and rear shims are the most popular but you can also purchase a thinner 3/16″ trim to fit shim for bridging issues or to fill behind wide shoulders.
  • Layering sets of shims will create an even transition for major saddle fit issues. Shims may also be cut with a pair of scissors for custom work.
  • Full Trim to Fit shims are available in 3/16 inch thin, or 1/4 inch of ThinLine protection.
custom saddle fit shims inserts

Layering sets of shims

How to order Saddle Fitting Shims with Saddle Pad.

Select a ThinLine Saddle Pad.  And you will see a product called “Trim to Fit Full Shim”, simply add the shims you need.

Image: Full Shim Inserted into Pad

The entire area under the ThinLine portion accepts up to 3 sets of 1/4 inch shims in one area. There are no “pockets”, allowing you to place stack and create gradual transitions between shims.

Saddle fitting with this with shock-absorbing foam provides balance, comfort, and protection for horse and rider.   Now you simply need to find the pad that fits the dimensions of your saddle and the style that fits your life.  Read on if you need more detailed saddle fitting information.

ThinLine is the only equestrian product endorsed by back surgeons, master saddlers & veterinarians.

Solutions for The High Wither Horse:

Our saddle pads come with a 4 inch wither profile with two exceptions: Basic Pads and the Pro-Tech Western.  All other pads work equally well on peaked withers and average horses. Simply Select your discipline:

Then, add a pair of Front Saddle Fitting shims- these will appear below your saddle pad.

Most high wither saddle fit issues are solved with a pad and a set of front shims.  ThinLine is sewn to the pad, supporting the saddle thereby providing both gullet (spine) and wither clearance.  If you have a horse with very narrow shoulders in addition to a high wither add a bridging shim to create the smooth transition and support the contact behind their shoulder.

Solutions for The Mutton Wither Horse:

Generally, saddle movement is the challenge with low withers. Saddles pitch, roll or slip forward. Non-Slip might be the first reason you purchase ThinLine but the noticeable improvement in comfort for your horse and the stability of the saddle will create more joy in your riding. 

We suggest a BASIC ThinLine,  or any ThinLine pad without shims.  Our Western Felt Pads are a favorite for low withers but all styles of ThinLine pads will be effective.  Unless your saddle is bridging or too low in the rear you most likely will not need saddle fitting shims.


western felt shock absorbing pad



Solutions for Saddles which Bridge or Horses with a Sway Back:

Any ThinLine Pad and Bridging Shims are the answer. Stack them then remove layers as your horse develops. It is not uncommon to see horses develop more topline in a ThinLine. Historically, riders eventually remove the bridging shim.  To retain the good muscle on the top line you’ve developed continue using your ThinLine without the shims.  

Bridging Shims are available for every ThinLine Pad. When you place a pad in your shopping cart scroll down to view the Trim To Fit shims which are sold in pairs.

Solution for Balance Issues Including Rear Riser Pads:

If you need to lift the back (cantle) of your saddle adding a rear shim to a ThinLine saddle pad is your answer. You may stack up to 3 sets of shims 1/4 inch shims to balance and protect.


Solutions for Asymmetrical (Crooked) Horses and Riders:

All of our shims are sold in pairs. If you have a crooked horse, simply place the pair on one side for severe issues, or simply use one shim.  Our research shows, horses lift their backs better in ThinLine resulting in eventual straightness.  Keep checking on your horses way of going and remove the shim once they are straight, continue using your ThinLine pad.

Solutions for Treeless Saddles and Horses in Intense Work

ThinLine works well with treeless saddles by providing support, integrity and shock absorption in a soft flexible product.

For horses in intense work we offer a full shim allowing owners to double the protection – Trim to Fit Shims, sold in pairs.


Master Saddlers and ThinLine developed a shimming system designed to create custom saddle fit while also providing shock absorbing therapeutic benefits. ThinLine saddle fitting shims are made from the same trademark foam found on ThinLine pads. In addition, shims are easily inserted or removed and stay in place during riding and washing. 

Now adjusting your saddle also includes more comfort. 



Using a ThinLine pad without saddle fitting shims will not alter custom saddle fit.

Easy to Install. Shims remain in place during riding and washing. Shims are invisible, inside your pad.


Front shim slips in to solve wither problems.
Create bridging fit; shim fills in gaps.

The full open panel allows you to place shims exactly where you need them.


Cotton Trifecta Half Pad
Contour Ranch Pad
Endurance Drop Rig Pad
Full Sheepskin Square Cotton Dressage Pad
Dressage full sheepskin
Saddle Seat Equitation Pad





Once you place a Thinline saddle pad in your shopping cart you will see below your cart, Add Trim to fit shims. Simply add the shims you need.


Front, Bridging or Rear Western Shims
Front, Bridging or Rear English Shims
Create them all from out Trim to fit shim.