The Acudor FW-5050-DW drywall, insulated fire rated access door is an enhanced FW-5050 that includes a galvanized steel drywall taping bead flange to facilitate installation in drywall. The Acudor FW-5050 is an insulated, fire rated access door approved for use in walls and ceilings. For walls, this door has an Underwriters Laboratories (UL and ULC), 1-1/2 hour "B" label, with a maximum temperature rise of 250 degress after 30 minutes. This door should be used in walls when temperature rise or heat transmission is a factor. For fire rated ceilings, this door has been approved by Warnock Hersey International for 3 hours (max. size t 24" x 36").