SERIES T18-500 – BALL FLOAT KITS SERIES T18-500 – BALL FLOAT KITS Ball Float Kits Red or White Polypropylene Ball improves visibility the level of liquid in a tube Red Balls fit our 5/8”OD & 3/4”OD Model 505 and 506 Tubular Glass Tubes White Balls fit our 1/2”OD Model 505 and 506 Tubular Glass Tubes Each kit includes one ball and a top and bottom PTFE insert