MTI SB4248 Center Drain/Rectangle Shower Bases, 42 inch x 48 inch Acrylic Shower Pans
Single, front threshold; 3.5" drain opening pre-drilled.
Durable Luciteฎ cast acrylic shell is extremely scratch- and stain-resistant, yet renewable because the color goes all the way through the material.
Non-porous surface makes cleaning and sanitizing faster and more effective.
Multi-layered backing of thick fiberglass / resin / titanium encloses wood reinforcement to prevent flexing of floor pan.
At least 30% thicker and stronger than other makes.
Pre-leveled with integral tile flange on 3 sides to facilitate installation.
Textured bottom that meets ASTM F-462-1994 certification requirements for safer showering.
10-year Limited Residential Warranty.
Made in the U.S.A.
You can find the current specs at http://mtibaths.com/media/specs/MTSB-4248.pdf
Please review the specs with your builder to make sure the base will fit before ordering.