There is a delicate balance that needs to be maintained with higher grade chalk: you need enough pigment to slap down a line that's not going anywhere and enough carrier to keep the chalk flowing. ProChalk Plus is formulated to achieve a perfect, lasting line every time.
ProChalk Permanent chalk for weatherproof and waterproof lines that aren’t going to go away any time soon. Most users are choosing this level of intensity for applications that are going to be covered. This level is engineered for more extreme conditions. Exterior applications include exterior layout, extreme conditions, concrete layout, long-term applications.
Keson Model No. PM8BLUEMER