Fire Classified Nonmetallic Rectangular Floor Box. Box comes complete with reusable mudcap, insert spacer, conduit plugs and reducers. Reducers provided for reduction to 1, 3/4, and 1/2 (25mm, 19.1mm, and 12.7mm) conduit. Minimum concrete depth is 3 1/2 (89mm) and maximum concrete depth is 6 (152mm). Minimum capacity is 50 cu. in. (819ml) and maximum capacity is 100 cu. in. (1639ml). Box dimensions are 4 1/8 W x 5 1/2 L x 6 (105mm x 140mm x 152mm). NOTE: Insert spacer should not be removed until after concrete pour. This is a single-gang offering. Cannot gang boxes together and maintain Fire Classification. Floor box spacing 2' on center, no more than 1 per 65 s.f. span. Maximum Copper Cross Section per Insert: Four (4) #12 AWG Type THHN Power Conductor or 48 #23 AWG (6 Cat. 6) Tele Data conductors. Box preserves the 2-hour fire rating of the floor in which it has been installed.