The top row and the first two insulators on the left of the 2nd row are all BUTTON TOPS. The rest are 3-Piece Molds of some type. Technically these are all 3-piece molds since the mold line does not go all the way across the dome. Here is some of the line-up. Some of the THREADLESS WITH A BUTTON TOP include:

CD 728.2 NO NAME with the "M" on the top; CD 729 NO EMBOSSING which the price guide (PG) does call out as a button; CD 729.4 NO EMBOSSING which the book calls out as a 3-piece mold; CD 729.6 PAT APP FOR; CD 731 McKee; CD 731 NO EMBOSSING "Stoddard style"; CD 731 NO EMBOSSING "McKee style"; CD 731 NO NAME with the "M" on the top; CD 731.3 NO NAME; CD 732 NO NAME;

Some of the THREADLESS WITH A 3-PIECE MOLD or no MLOD include:

CD 701 NO EMBOSSING "Sandwich Egg" & all the other egg styles; CD 701.2 NO EMBOSSING; CD 701.5 NO EMBOSSING; CD 701.6 NO EMBOSSING "Confederate Egg"; CD 701.8 NO EMBOSSING "National Road Egg"; CD 723.5 NO EMBOSSING; CD 723.6 NO EMBOSSING; CD 724 NO EMBOSSING & CHESTER; CD 725 NO EMBOSSING; CD 728.5 NO EMBOSSING "Lyndeborough CD 134 Counterpart"; CD 732.2 NO EMBOSSING (has the classic 3-piece dome); CD 732.2 PATENT DEC 19, 1871 (has the classic 3-piece dome); CD 734.1 NO EMBOSSING (my two do not have MLOD, may need to add to or change PG); CD 735 TILLOTSON; CD 735.7 NO EMBOSSING "Big Blue"; CD 736.4 NO EMBOSSING (my two do not have MLOD, may need to add to or change PG); CD 736.5 NO EMBOSSING (my two do not have MLOD, may need to add to or change PG); CD 737.5 NO EMBOSSING (mine does have MLOD, may need to add to or change PG); CD 739 NO EMBOSSING "Big Blue" (my two do not have MLOD, may need to add to or change PG); CD 739.5 NO EMBOSSING "washboard and smooth dome"; CD 740.6 CHESTER; CD 780 NO EMBOSSING; CD 790 & 791 "teapots" have MLOS but no MLOD, you figure it out!!!! LOL