For parents looking for a secure metal gate that will fit in those larger openings between 3.5 and 6 feet wide, there's the Summer Infant Sure&Secure™ 6 Foot Metal Expansion Gate.  The hardware mounts securely in place and has a convenient walk-thru door for easy access between rooms. 

Featuers:

Fits openings 44”-72”(106cm-183cm),stands 30” (76cm) tall

Secure hardware mounted design

Great for double doorways and extra-wide openings

One-handed stylish arched walk thru door

4 extensions included

Three language packaging