Sig P211 Fitment Guide: GTO / GT4 / GT5 Springs, Fat Rod, Comp, Magwells & Parts
Posted by Fdez Werx on 27th Oct 2026
This guide is the fitment companion to our P211 GTO / GT4 / GT5 upgrade and tuning post. It focuses on what fits which sub-model: recoil springs, the HD fat rod, sight block / comp delete, magwells, trigger, beavertail, OEM small parts, and porting services.
The Sig Sauer P211 platform includes the GTO, GT4, and GT5. The trigger, magwells, grip, and all small parts fit all three regardless of variant; recoil springs and the fat rod are length-specific.
The P211 Full Size is the same as the GT5, and the P211 Carry is the same as the GT4. The only difference is that the Full Size and Carry use a polymer grip, while the GT4 and GT5 use an aluminum grip with removable grip panels. Wherever this guide says GT5, that also covers the Full Size; wherever it says GT4, that also covers the Carry.
1. Quick Fit Rules
- Drop-in fit: all Fdez Werx P211 parts are drop-in fit, except a thumb safety, which requires gunsmith fitting.
- Full Size and Carry: Full Size = GT5 fitment, Carry = GT4 fitment. They differ only in the polymer grip (GT4/GT5 use an aluminum grip with removable panels).
- Slide and frame swaps: a GTO slide assembly can be used on a GT4 or GT5 frame, and a GT5 slide assembly can be used on a GTO or GT4 frame and grip. A GT4 slide is the same overall length as a GTO slide without the comp. Use the recoil spring that matches the slide.
- Trigger, grip, and small parts: fit GTO, GT4, and GT5 regardless of variant.
- HD Fat Rod & Plug: GTO, GT4, and Carry (not GT5 or Full Size). Works with OEM and Fdez recoil springs. Does not work with Sig Guy springs.
- Recoil springs: GTO/GT4/Carry use 8 / 10 / 13 lb. GT5 and Full Size (5") use dedicated 8 / 10 lb springs.
- Sight Block Comp Delete: installs on the factory GTO barrel and muzzle attachment. A GTO barrel can be used in a GT4 (or Carry) slide to run the comp or the sight block.
- Adjustable trigger, grip safety delete beavertail, Series 70 filler plate, magwells: fit GTO, GT4, and GT5.
- Adjustable trigger: reduces pre-travel and over-travel; does not change pull weight by itself. Lowering pull weight needs further trigger-component work. The polished bow improves smoothness and feel.
2. Recoil Springs
| Spring | Fits | Typical use | Shop |
|---|---|---|---|
| GTO/GT4 8 lb | GTO, GT4, Carry | Light / ported / compensated setups | Shop |
| GTO/GT4 10 lb | GTO, GT4, Carry | All-around 115–147 gr / match | Shop |
| GTO/GT4 13 lb | GTO, GT4, Carry | Full-power duty loads | Shop |
| GT5 8 lb | GT5 and Full Size (5") only | Lighter GT5 setups | Shop |
| GT5 10 lb | GT5 and Full Size (5") only | Standard GT5 setups | Shop |
Do not install GTO/GT4 springs in a GT5, or GT5 springs in a GTO/GT4.
3. HD Fat Rod & Plug
| Part | Fits | Does not fit / notes | Shop |
|---|---|---|---|
| P211 GTO / GT4 Heavy Duty Fat Rod and Plug | GTO, GT4, Carry | Not for GT5 or Full Size (a GT5 fat rod is coming soon). Works with OEM and Fdez springs; not with Sig Guy springs. Material (as listed): 17-4 stainless steel, high polished, DLC coated. | Shop |
4. Sight Block / Comp Delete
| Part | Fits | Notes | Shop |
|---|---|---|---|
| P211 GTO Sight Block Comp Delete | GTO, or a GT4 / Carry slide fitted with a GTO barrel | Installs on the factory GTO muzzle attachment. Hardened stainless, weight-matched to the OEM comp. Reuses OEM taper wedge pin, spring, and set screw; ships with a spare hollow set screw. Clean carbon off the barrel end before install. | Shop |
| Comp Replacement Set Screw and Spring | GTO comp / sight-block hardware | Replacement factory-style hardware | Shop |
| GTO OEM Compensator Taper Wedge Pin | GTO | OEM taper wedge pin | Shop |
5. Magwells
| Magwell | Fits | Notes | Shop |
|---|---|---|---|
| Light Weight Magwell | GTO, GT4, GT5 | 7075-T6 aluminum, ~0.6 oz | Shop |
| Brass Magwell | GTO, GT4, GT5 | Naval brass; same weight as the OEM steel magwell | Shop |
| OEM Magwell Screw | P211 magwells | OEM replacement screw | Shop |
6. Trigger, Beavertail & Series 70
| Part | Fits | Notes | Shop |
|---|---|---|---|
| Adjustable Trigger | GTO, GT4, GT5 | Independent pre-travel and over-travel adjustment without disassembly. Does not change pull weight by itself. Polished bow for smoother feel. | Shop |
| Grip Safety Delete Beavertail | GTO, GT4, GT5 | No frame drilling. Deletes grip-safety engagement for competition-style draws. | Shop |
| OEM Beavertail Grip Safety | GTO, GT4, GT5 | Factory-style grip safety | Shop |
| Series 70 Conversion Filler Plate | GTO, GT4, GT5 | Replaces the firing-pin block lever when converting to Series 70-style operation | Shop |
7. OEM Small Parts
Common OEM replacements stocked for P211 builds and service. Every part below fits all P211 variants (GTO, GT4, GT5, Carry, and Full Size), except the lower grip screw, which fits only the aluminum grips on the GTO, GT4, and GT5 and does not fit the Carry or Full Size polymer grips.
| Part | Shop |
|---|---|
| Extractor / Extractor Pin / Extractor Spring | Extractor · Pin · Spring |
| Firing Pin | Shop |
| Sear / Sear Pin / Sear Spring | Sear · Pin · Spring |
| Safety Lock Plunger / Plunger Spring | Plunger · Spring |
| Mainspring / Cap / Cap Pin / Housing | Spring · Cap · Cap Pin · Housing |
| Barrel Link / Link Pin | Link · Pin |
| Ambi Hammer Pivot Pin | Shop |
| Lower Grip Screw (GTO, GT4, GT5 aluminum grips only; not Carry or Full Size) | Shop |
8. Porting Services
| Service | Fits | Notes | Shop |
|---|---|---|---|
| GTO Porting Service | P211 GTO | Send-in porting; lead time about 7–10 business days (1–2 weeks) from when we receive your item, plus shipping | Shop |
| GT4 / GT5 Porting Service | P211 GT4, GT5 | Same send-in lead-time wording as above | Shop |
9. FAQ
Does the HD fat rod work with my OEM spring?
Yes. It works with OEM and Fdez springs. It does not work with Sig Guy springs.
Will the adjustable trigger lighten my pull?
No, not by itself. It reduces pre-travel and over-travel. Changing pull weight needs further trigger-component work.
Can I put the Sight Block Comp Delete on a GT4 or GT5?
Yes on a GT4 (or Carry) if you swap in a GTO barrel, since it installs on the GTO barrel and muzzle attachment. It does not install on a factory GT4 or GT5 barrel.
Which recoil spring should I start with?
GTO/GT4: 10 lb is the all-around starting point for 115–147 gr. Use 8 lb for lighter / ported / comp setups and 13 lb for full-power duty. GT5: choose between the dedicated 8 lb and 10 lb springs.
Browse P211 Performance Parts, OEM Parts, and Custom Services, or read the upgrade and tuning guide.