This is a gallery, cre­at­ed with the default Word­Press Gallery Option. The Image size of gallery pics is set auto­mat­i­cal­ly when the theme is acti­vat­ed, all you have to do then is to insert a gallery with a max of 7 columns to make it look like the one below…

Gallery with Preview

Small Thumb Gallery

You can choose which Pre­view Image size you want to dis­play and also how many thumb­nails should be dis­played with­in one row. Also notice the sub­tle ani­ma­tion effect that starts once the vis­i­tors screen has reached the Gal­leries, to draw his atten­tion :)

Bigger Gallery with Preview