Zero International 318BK Perimeter Seal with Sponge Neoprene

The 318BK ships as a complete set for a single standard opening: one 36 inch head piece and two 80 inch jamb pieces. That covers the head and both jambs. It does not seal the bottom of the door, so if you need the threshold side covered you will need a separate door bottom or sweep.

Fire rated to UL10c, and it also carries air seal and smoke seal ratings. That combination is what a labeled opening in a hospital, school, or multi-family corridor typically calls for on the frame perimeter.

The extruded housing is 1 inch wide and .408 inch high. That is the footprint you need on the stop face of the frame, and the .408 projection is what closes the gap between the stop and the door face once the sponge neoprene compresses.

Three different jobs. The 318BK uses closed cell sponge neoprene, which compresses to block air and smoke and is what you want on a rated or acoustic opening. A nylon brush seal like the NGP 602A sweeps the gap and tolerates constant door movement but does not seal air tight. A magnetic seal such as the NGP 159MA pulls itself to a steel door for a tight acoustic closure, which only works if the door is ferrous. Vinyl inserts, like the NGP 155V or the Cal-Royal PG-601, are the general purpose weatherstrip choice.

No. The NGP 602A is a nylon brush seal in an anodized aluminum housing, and a brush element sweeps debris and air but does not compress into a continuous closed seal. The Zero 318BK is a compression-type adjustable sealing system with closed cell sponge neoprene, which is what suits sound control work. Use the 602A where a sweeping brush is what the job wants, not as a drop-in for the 318BK.

The Zero 318BK is the one to specify when the opening is fire rated. It is listed to UL10c and is also air seal rated and smoke seal rated, so it covers a fire door that additionally needs smoke and air infiltration control. The comparable perimeter and brush seals are described by their sealing material and frame rather than by a fire listing, so confirm the label requirements before swapping one in.

Screw mount. The aluminum carrier is fastened to the frame stop, which means you can back it off and reset it to fine tune compression against the door, unlike an adhesive-backed seal. Screw mounting is also what lets it hold up on a high traffic commercial opening.

Sponge neoprene is a closed cell material, so it compresses fully against the door face and seals the perimeter gap rather than just brushing it. Zero builds these as adjustable sealing systems for sound control work, and the same closed cell seal is what earns the air and smoke ratings. For a real acoustic assembly you still need the bottom of the door addressed with an automatic door bottom or seal.

The closest match is the NGP 108NA, a neoprene sponge seal in an anodized aluminum frame, rated for a temperature range of -20 F to 200 F. Same construction idea as the 318BK, sponge neoprene carried in an anodized aluminum extrusion. If you are standardizing a building on one seal, either will give you the same compressible closed cell perimeter, though you should confirm the rating you need on each opening.

Two options carry a vinyl sealing element rather than sponge neoprene. The NGP 155V is a vinyl perimeter seal in a mill aluminum frame for commercial door weatherstripping, and the Cal-Royal PG-601 is an aluminum channel perimeter gasketing with a vinyl insert. The Zero 318BK instead uses closed cell sponge neoprene in a clear anodized aluminum housing, so if the spec calls out vinyl specifically, the 155V or PG-601 answers it.

The NGP 159MA is a magnetic seal in anodized aluminum, supplied in an 84 inch length. It seals by magnetic attraction to the door face rather than by compressing an elastomer, which is a different closing action than the Zero 318BK, whose closed cell sponge neoprene compresses against the door. Note the 159MA is a single 84 inch piece, while the 318BK is supplied as a set of one 36 inch and two 80 inch pieces to dress a full frame.

The Cal-Royal PG-601 is aluminum channel perimeter gasketing with a vinyl insert, so it does the same head-and-jamb sealing job as the Zero 318BK even though Cal-Royal groups it in their Door Shoes series. The difference that matters on the order is the sealing element: vinyl insert on the PG-601 versus closed cell sponge neoprene on the 318BK, which is the compressible material suited to sound control openings.

Black anodized, in a 72 inch length. Note that the housing material itself is aluminum with a clear anodized base; the BK designation is the black anodized option, which is the usual pick when you want the seal to disappear against a dark frame or a dark painted stop.

It is built and catalogued as a commercial product. Nothing stops it going on a residential door, but the screw-applied aluminum housing and the UL10c rating are aimed at labeled and high traffic commercial frames. For a house door you are paying for smoke and fire performance you will not use.

The Zero 318BK set is clear anodized aluminum and is offered in a black anodized finish option. Among the alternatives, the NGP 108NA and NGP 602A use anodized aluminum housings and the NGP 159MA is anodized aluminum as well, while the NGP 155V uses a mill aluminum frame. Mill aluminum is an unfinished extrusion, so it will read differently against a finished frame than an anodized housing will.