Great comment danickstr and I do than quite often, which always gets a blank stare from the inspector, in residential work. Unfortunately, Lamson & Sessions, (the Carlon blue box people), stop at their 32 cu. in. B432A 4" square box which doesn't solve much in bathrooms & front doors. Their BH235A 35 cu. in. box won't accept a raised cover.
Last July I sent the blue box people pictures of variations to their line which would give us more space in crowded boxes. I suggested they offer trimmable blank plastic covers and trimmable three gang raised covers in their 3 & 4 gang line (B344AB & B455A-UPC). If crowding became a issue the electrician could simply install a 3 gang raised cover on a 4 gang nail-on box and trim off 1 gang of blank cover from his "cover stock" and fill the space.
He would then have an extra 32 cu. in. available in the box and an extra 9.6 cu. in. available because of the 3G (1/2") raised cover.
Since they already offer 2 G raised blue covers we could trim down and drill one of their 4" square blanks, but the modification would not be UL listed.
The other alternative is to use commercial metal boxes and covers, which would send us to the poorhouse.
