Question: are legos and mega construx compatible?
Answer: The studs of bricks from LEGO System and Mega Construx (f.k.a. Mega Bloks) are compatible, but other connections are not: ... 18”), but Mega Construx bars are slightly narrower. Hence, many MC accessories and decorative elements will be loose if placed in LEGO clips or hollow studs, and LEGO bars will not fit in MC.