Linked benefit account

I’ve been talking to a tax specialist about tax reduction in retirement. He suggested a tax reduction strategy called a “linked benefit account” the is set up inside your retirement portfolio (could be at Fidelity or Vanguard). It has an insurance portion to it. Seems somewhat similar to an annuity but as he explains it there are some pretty good tax benefits on a 600k (over 5 years) investment. Has anyone heard of this and is it worth considering? Thank You.