Simmons also used the WP stamp on aftermarket rib jobs if requested. However, a late serial number Model 42 with Skeet choke barrel that has not had a solid rib removed to install the Simmons rib is likely a Simmons marketed gun, not a retrofit rib job. The reason for this is that a late number Model 42 that started life as a plain barrel Skeet choke gun is not likely to be sent out by Winchester in that configuration because plain barrel Skeet Grade guns are mostly a prewar catalog item.