Measure the gap between the roughed-in drainpipe and the bottom of the shower pan. Measure the length of the drain body and saw off any portion of the drainpipe that would interfere with the drain body’s fitment.
Brush PVC primer on the inside of the bottom portion of the drain body and the outside of the top of the drainpipe. Allow the primer to dry and brush PVC cement onto the drainpipe and drain body, then slide the drain body over the drainpipe.
Insert your fingers into the drain opening in the shower’s floor from inside the shower. Move the drainpipe to the side slightly, using your fingers.
Use your other hand to insert the rubber gasket and metal washer, if one came with your drain assembly, onto the lip on the top of the drain body. Carefully release the drainpipe with your fingers, allowing it to return to its original position.
Spread an even amount of caulk on the underside of the drain strainer’s lip. Thread the strainer into the drain body through the drain hole in the shower pan.
Tighten the strainer into the drain body by expanding a drain key inside the strainer and using an adjustable wrench to grip the top of the drain key and turn it clockwise.
Place the cover on top of the drain strainer. Drive the anchor screw through the hole in the cover and into the screw hole in the drain body.
Tighten the screw until the cover stays securely in place.