Cheapest method to whiten those yellowing BOOST midsole?
Using a Marker. Period.
But which marker? That is the question. A relatively new brand in UK released one of the first whitening BOOST midsole pen back in 2016, and the ingenuity of it propelled the brand to fame with hundreds of thousands of customers using it to whiten the yellowing BOOST midsole.
In 2017, we saw several other brands creating their own version of the BOOST Midsole Pen but the biggest one of them all was the white Sharpie marker! It was not intended for BOOST midsoles but creative fams out there saw another use for it and tried on their BOOST with relatively good effect.
SHOULD YOU USE AN ACRYLIC BASED PEN OR OIL-BASED PEN?
In my humble opinion, an acrylic based midsole pen by some of the major brands out there should be your choice. While everything is equal, only an Acrylic Based pen gives you the proper shade of white color that makes your BOOST looks authentic. A Sharpie pen turns your BOOST blindingly white with a glossy sheen, making it look fake. An acrylic based midsole pen however is slightly off-white (which is similar to original BOOST) and has a matte finish.
WHICH IS CHEAPER?
Sharpie, hands down. You can't compete with the price of a manufacturer who makes them in the millions. However, SNEAKERGUARD, one of the newer brands in the Midsole Pen category, recently released a new BOOST Midsole Pen in MINI size! At around half the size of a normal sized Midsole Pen, it contains enough ink to use on 1-2 pairs of sneakers. It also retails for around USD9.0, making it the cheapest Acrylic Based Midsole Pen in the market right now.
The size of the MINI Midsole Pen is the same as a Sharpie Pen.
SNEAKERGUARD's BOOST Midsole Pen - White (MINI). It has enough ink to cover 1-2 pairs of sneakers and comes at a very affordable price. Though slightly more expensive than the Sharpie, the quality of the finish more than makes up for it.