GrovTec US Recessed Plunger Heavy Duty Push Button Swivels Black. The release buttons on this swivel set come flush to the swivel body virtually eliminating the chance for errant release of the swivel. Featuring extremely tight machining tolerances and pull tested to over 450 pounds of tension. Specifications for GrovTec US D-Loop Recessed Plunger Heavy Duty Push Button Swivel Set: Manufacturer: GrovTec US Color: Black Fabric/Material: Steel Gun Type: Rifle Gun Model: Universal Condition: New Package Contents: GrovTec US D-Loop Recessed Plunger Heavy Duty Push Button Swivel Set GrovTec US GTSW287: Recessed Plunger Heavy Duty Push Button Swivels Black