17 seals made primarily of elastomers for blowout preventers; rebuild kits for seals made primarily of elastomers for blowout preventers, comprising packings, seals, bonnet seals, O-rings, lip seals, piston seals, adapter seals, rod seals, packing rings, plastic packings, wear bands, wear rings, retainer rings, washers, bleeders, screw sets, plugs, and tubing