Sylvan Arms AR15 Lower Vise Block Module SPECIFICATIONS BRAND: SYLVAN ARMS CA PROP 65: YES CA PROP 65 CHEMICAL: LEAD DESCRIPTION The super durable, chemical-resistant lower support module allows you to hold your firearm securely for cleaning, assembly, and repair. This support module slides easily and fits firmly into its corresponding Sylvan Arms cleaning plate thereby safeguarding against finish and structural damage that may be brought on by the application of vise pressure such as scratches, dents, twists, and other structural distortions.