In general, klister is required for classic skiing on waxable skis when the snow is icy, slushy or really wet. With these conditions, snow will not stick into the hard wax, which results in no kick.

What is klister wax used for?

Klisters are the stickiest kick waxes. They're so sticky they come in a tube, like toothpaste. Klister is the best way to get grip in super icy snow or in very warm, wet snow. Klister is often viewed as a huge pain to use but it can actually be used just as easily as any hardwax.

Can you put hard wax over klister?

You want to put a thin layer of hard wax on top of the klister, but not mix them. Start with one or two layers of a hard wax rated warmer than the temperature, then coat with a few layers of a harder wax rated for the temperature. The idea is to get the grip from the klister, but stop icing with the hard wax.