#279XT Smoke Spec (does not include lenses) The #279XT Smoke Spec insert with extension bracket. Click here for the Smoke Spec Insert Guide for examples of compatible masks. Click here for insert specs. Instruction Page #279XT Smoke Spec quantity Add to cart Category: Uncategorized Related products Additional Anchor Bracket (does not include lenses) Add to cart #276XT Smoke SpecThe #276XT Smoke Spec insert with extension bracket. Click here for the Smoke Spec Insert Guide for examples of compatible masks. Click here for insert specs. Instruction page. (does not include lenses) Add to cart