Oatey offers a wide variety of covers that include supply line and stop covers, offset drain covers and P-trap covers.     
With the exception of the P9703 and P9703BG, all of our plastic tubular products come with the True Blue washer. The P9703 and P9703BG come with the polyethylene rigid washer. All brass tubular products come with a square cut rubber washer, which performs better on the chromed surfaces.  
True Blue is IAPMO listed. True Blue won’t dry out or crack. This ensures long, leak-free protection. True Blue has superior flex fatigue protection, which extends the life of the washer. True Blue has advanced Thermoplastic Elastomer (TPE) properties. This allows the True Blue to retain its shape when the traditional polypropylene washer may not. Overall; the Ultra flexible elastomer washer combined with the tapered design, provides the end user with ultimate leak protection.
An Air Gap product is designed to be installed in to the countertop in some municipalities when a dishwasher is being installed. The hose from the dishwasher will connect to the inlet side of the air gap, then a separate hose will be installed between the outlet side of the air gap and the disposal or dishwasher tail piece. Check with your local building officials before installing your dishwasher because air gaps are not required in ever municipality.
No. The S-Trap is not approved for any installations that require a plumbing permits and or inspections.
No. The Form-N-Fit is not approved for any installations that require a plumbing permits and or inspections. 
If you have a disposal installed in your kitchen sink, the dishwasher drain can be connected to the ¾” drain port designed into every residential disposal. If a disposal is not available for a drain connection, Oatey offers several styles of dishwasher branch tail pieces for this application. You can find these available tail pieces in category 15 in the Oatey catalog or on our website.
No. The polypropylene materials cannot be assembled with solvent cements, they have to be assembled with the slip nuts/washers.
Yes. The N.Y. Code and L.A. Code traps are designed to work for this application.
The most common tubular product sizes are 1¼” and 1½”. These sizes are available in brass and plastic tubular products. The trap adapter connection to the branch drain in the wall will determine the largest size of tubular product which can be connected with a slip nut and washer. This point of connection can also be reduced for 1¼” tubular assemblies, with a reducing washer and slip nut. Bathroom sink installations are normally completed with 1¼” tubular products, but 1½” tubular products will also work. Kitchen sink installations can only be completed with 1½” tubular products.