The Slug Gun series sights are fiber-optic replacement sights for factory dovetails at manufacturers specifications. This sight set is compatible with Remington Slug barreled shotguns with dovetail sights. Front Fiber Diameter: 0.035". Rear Fiber Diameter: 0.035".
Specifications:

Type	Fiber Optic Front/Rear
Frame Material	Steel
Frame Color	Black
Firearm Fit	Remington 870/1100/1187
Base Configuration
Style	3 Dot
Front Material	Fiber Optic
Rear Material	Fiber Optic
Front Color	Red
Rear Color	Green
Rail Size
Windage Adjustment	Yes
Elevation Adjustment	Yes
Fiber Diameter	.035"
Firearm Type	Shotgun