How are 100% buffers implemented?

I notice there are some buffered ETFs that offer "100% downside protection" in return for limited upside. I'm not looking to trade ETFs but rather I'm asking a technical question on how this is done so that I can possibly implement buffers in my trading. The best I can come up with is e.g. Buy 100 shares of NVDA at price = 150 Sell 1 call, strike = 160 Buy 1 put, strike = 150 Sell 1 put, strike = 140 However, this does not provide 100% downside protection, it only provides downside protection from 140-150 which is only 7% of the 0-150 range. How do I implement true 100% downside protection like the ETFs do?