The correct spark plug and gap is crucial to proper ignition. Spark discharge is a breakdown in the air insulator between the electrode and ground. Yes - air is an insulator, a pretty good one at that. As voltage builds at the electrode, atoms in the air within the air gap gain electrons. This process is called ionization.
It's one of the reasons why our standard lenses are polycarbonate (thinner than standard lenses typically sold by other eyeglasses retailers). At Warby Parker, you can upgrade to high index lenses for an additional $30 whereas it typically costs $60 to $100 more.
Cost : $800 to $1000 for a pair of hard lenses; $98 per box of 30 pieces (15 pairs) of daily disposable soft lenses; and from $145 to $160 for a box of six pieces (three pairs) of monthly disposable soft lenses. For monovision, one eye is corrected for far vision and the other is corrected for near vision.