WISECO ATV-DIRT BIKE PISTONS. * All Wiseco 4 cycle pistons come complete with rings, wrist pins and circlips. * Only Wiseco replacement ring sets can be used on Wiseco pistons. * All Wiseco 2 cycle pistons are supplied with rings and circlips. * Wiseco 2 cycle pistons are not supplied with a wrist pin unless noted in the description.