The WHIRLYGIG method of manhole riser/collar installation is size accurate, installs in minutes and leaves no doubt about quality control. Simply place a form on the manhole cone, trim the form to grade with the radial arm trimmer, place the manhole ring, check accuracy and pour Redi-mix. The system streamlines installation into a process that works every time and produces a sturdy installation. 800/307-4263; www.wgig.us.