Nope. Seidlemann is completely different brand. S2's were built in Hollan MI by Leon Slikkers, one of the original fiberglass boat builders. Slickers sold SlickCraft to AMF in the 70's and had a non-compete for a decade. Since he couldn't build power boats he switched to sailboats for his second effort, appropriately names S2. Once the market went sound in the mid 80's and his non-compete was up he started Tiara. Tiara yachts cost about twice as much as a Searay. The fiberglass work on S2's is amazing for the time. Most boats look half their age from a spider crack perspective. The 27 is a nice racer cruiser and is one of his last sailboat designs. About 85 hulls were built.