The elastomeric sealants are manufactured from polysulfide polymers. These cure by polymericzation, a linking of the molecules end to end. This linking produces exceptionally long chain molecules and provides the polysulfide systems with their rubber and elastic-like qualities. Polysulfide polymers have very few ether bonds and therefore are not strong in bond. It is up to the formulator, then, to formulate an adhesive into his system. Since each formulator has his own system, it is essential that tests be made to determine the effectiveness of the bond of a particular polysulfide polymer system before it is used. This way weak bonding systems can be eliminated before they are used and start creating problems. To provide the elastomeric qualities required of the polysulfide sealants, they are generally manufactured with a Shore hardness of 20-25 on the A scale. This is quite soft and should not be used in foot traffic areas since ladies' heels can penetrate it quite easily. If it is essential to have a material of this hardness, due to the excessive movement of the joint slot, then the slot should be protected by means of a metal plate. In order to resist indentations form ladies' high heel shoes in foot traffic areas where the joint slot is not subject to movement but merely to flexing, a very good flexible joint filler with excellent adhesion and a Shore hardness of 50 on the A scale can be formulated with an epoxy system. If the joint does not move but the sealant is merely used as a joint filler, then a material with a much higher Shore hardness can be used. Polysulfide polymer joint sealants are usually manufactured in two grades: a nonsagging type for vertical and overhead joints and a self-leveling type for horizontal joints. In order to make the edges of horizontal joints neat, masking tape can be applied to both sides of the joint slot before pouring the polysulfide joint sealer. As soon as the sealant has been poured and has leveled itself, the tape should be stripped off, thus leaving a neat edge to the joint slot.