Evolution Gun Works Bobtail Regrets Mainspring Housing 25 LPI Kimber Colt 1911 Steel Stainless. Want your grip to feel full again? We have the perfect solution for you. Our Bobtail Regrets Mainspring Housing has the pin located high so that it works with frames that have been made or modified to have a bobtail grip. This will not work on frames with the hole in the standard location.The checkering on this mainspring housing helps get the weight in the right place and gives you good traction.Pins and springs do not come with this part. You can use the pins and springs from your original mainspring housing or purchase new parts from us.This mainspring housing makes a great replacement for plastic mainspring housings.This is our premium mainspring housing designed and made by EGW. Fully machined from bar stock and then glassbeaded. This item will fit 1911 Government and Commander frames it will not fit STI's or short grip frames. It is a flat mainspring housing. Specifications for Evolution Gun Works Bobtail Regrets Mainspring Housing 25 LPI: Manufacturer: Evolution Gun Works Fabric/Material: Steel Design/Pattern: Checkered Gun Make: 1911 Platform Gun Model: Colt 1911 Kimber 1911 Condition: New Package Contents: Evolution Gun Works Bobtail Regrets Mainspring Housing 25 LPI What firearm models does the manufacturer say Evolution Gun Works Bobtail Regrets Mainspring Housing 25 LPI is compatible with? The manufacturer suggests that Evolution Gun Works Bobtail Regrets Mainspring Housing 25 LPI is compatible with Kimber 1911 Colt 1911Evolution Gun Works 11450: Bobtail Regrets Mainspring Housing 25 LPI Kimber Colt 1911 Steel Stainless