Has been around all my 50 odd years in the DO. Ther are many options for the dimension line end connection to the leader, filled arrow, open arrow, slash, dot et al. The one chosen is set by company standard and industry choice, architects very often use the slash, while engineers use the closed arrow. Take you choice but stick to one, although in some circumstances a different form may be used on a drawing where the normal one used is too large for close dimension lines.