It’s not every day that you see a really large sperm on a really large bike. But starting next week, it’s going to become commonplace — at least in Seattle.

The sperm is a white hollowed-out piece of fiberglass with a freezer compartment to store donor sperm. The 10-foot bike weighs upwards of 50 lbs. and has a wriggly sperm tail protruding from its rear end. The rider will shuttle the sperm-within-a-sperm to local fertility clinics.

The bike is an unabashed marketing gimmick (and an environmental statement) for Seattle Sperm Bank, also known as European Sperm Bank USA. An identical bike plies the streets of Copenhagen, where the bank’s sister branch resides. Stares are welcome: it’s hoped that the bike will spur a conversation about sperm banks and the need for high-caliber sperm donors.

It’s fitting that the sperm bike makes its U.S. debut in Washington State, home to a controversial new law that guarantees that children conceived with gametes from Washington sperm banks and egg donation agencies will have access (when they’re 18) to their donors’ medical histories and their full names — unless the donors specifically opt out of being identified.

A good donor apparently is hard to find. European Sperm Bank USA has a three-step application for 18-to-39-year-olds who want to donate sperm. Following a sperm-quality analysis, just a paltry 5% to 10% of would-be donors make it to the next step: a genetic family-history interview. A physical exam and blood test are the final stage. “Most people associate sperm banks with a joke,” says Gary Olsem, the bank’s managing director. “There’s porn there, and they think it’s a dirty thing, when in reality it’s very clinical like giving blood.”

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This week, Seattle Sperm Bank staff members are taking turns riding the bike. (Incidentally, it’s only the latest in saucy unmentionables-on-wheels; in Pittsburgh, an artist recently designed a “mobile breast-feeding unit” — essentially a breast atop an old milk truck — that zooms to the rescue of mothers being persecuted for nursing in public). Next week, the sperm bank will start deliveries, loading up to 20 vials of $500-$600 semen into the sperm tank, where liquid nitrogen keeps it at a chilly -120 to -150 degrees Celsius.

Seattle may not have the steep-sloped reputation of San Francisco, but it’s very bit as hilly, so the bike is also equipped with a small motor for an extra boost if need be. But perhaps the biggest challenge in being the sperm bike cyclist is learning to focus on the road and not the open mouths of passersby. In their test runs, riders have been amused by people’s reactions, which have run the gamut. “Once they figure out what it is, they’re either shocked or they think it’s a hoot,” says Olsem. “But definitely everyone who walks by turns their head.”

Bonnie Rochman is a reporter at TIME. Find her on Twitter at @brochman. You can also continue the discussion on TIME‘s Facebook page and on Twitter at @TIME.