The Sunday Cat retains the large cockpit of the day sailer, but employs a small cuddy cabin that can accommodate a portable head.

[1][3] The design has been built by Com-Pac Yachts in the United States starting in about 2008 and remained in production in 2019.

It has a cat rig with a single gaff-rigged sail, a plumb stem, a nearly vertical transom, a transom-hung rudder controlled by a wooden tiller and a stub keel, with a retractable stainless steel 80 lb (36 kg) centerboard.

[1] The mast, boom and gaff are designed for quick raising and lowering, while on the trailer or while afloat.

All spars remain attached and lower onto a transom-mounted boom gallows.