PCR-Cooler keeps samples in 0.2mL PCR tubes or plates at 0ºC for over 1 hour and between 0ºC and 7ºC for approximately two hours. A change of colour from purple to pink or dark blue to light blue lets you know when the temperature exceeds 7ºC. Use to prepare cycle sequencing reactions, restriction digestions, or prevent non-specific primer annealing. Pre-chill before use. Package of two colours includes one of each, blue and pink.