It's now only a matter of hours until the Uber IPO drops. Uber is going to be a monster; the famous ridesharing company anticipates it will rake in a dizzying $8.5 billion or so in its issue.

The IPO market is red hot now, thanks to Uber and recent high-profile issues for companies such as rival Lyft (NASDAQ:LYFT) and alt-food producer Beyond Meat (NASDAQ:BYND). Here's a look at four more of the many new stocks that are slated to debut in May.

The letters "IPO" cut out of a dollar bill.

Image source: Getty Images.

HeadHunter Group

The aptly named HeadHunter Group is an executive search company with a twist that will be unique on our markets -- it concentrates exclusively on Russia and the Commonwealth of Independent States (CIS).

It makes its money in traditional ways for its industry, taking a fee from both potential hires and employers to access its databases. HeadHunter Group also provides consultancy services to some of its clientele.

The company is seeking to raise as much as $220 million in its IPO. The shares should start trading Thursday, May 9, on the Nasdaq under the ticker symbol HHR.

Postal Realty Trust

Another unique upcoming issue is Postal Realty Trust, a real estate investment trust (REIT). Postal Realty Trust concentrates exclusively on, you guessed it, properties that are leased to the U.S. Postal Service.

All told, Postal Realty Trust operates 271 properties spread across 41 American states. It plans to acquire more when they become available.

It's quite profitable -- the most recent annual figures for the pre-IPO configuration show nearly $7.7 million in revenue and adjusted funds from operations (AFFO) of just under $3 million. Both results were up on a year-over-year basis.

Postal Realty Trust will gross as much as $105 million from its IPO if its shares price at the top of their range. The ticker symbol will be PSTL, and the first day of trading for the stock is scheduled for Friday, May 10, on the New York Stock Exchange. That's the same day as the Uber IPO, so to put it mildly, this one might fly under investors' radar.

Bricktown Restaurant Group

The hands-down winner of the Best Ticker Symbol prize among the May IPO crowd is Bricktown Restaurant Group. Once listed on the Nasdaq, the company's stock will trade under the tempting designation of BEER.

This is wonderfully self-descriptive. Bricktown operates craft beer-centered pubs and restaurants under two respective brand names, Bricktown Brewery and Bricktown Tap House & Kitchen. At the moment, there are 14 such establishments located across five states -- Texas, Arkansas, Kansas, Oklahoma, and Missouri. Most are company owned.

Collectively, the 10 or 11 pubs/restaurants that were in operation in fiscal 2017 and 2018 (one was sold) booked net revenue of nearly $30 million. The company posted net losses in both years.

Bricktown plans to grow the old-fashioned way, by expanding its footprint. It would like to build out in its current areas of operation and perhaps expand more widely.

BEER's glass will be relatively small -- it stands to rake in a maximum of $17 million in the IPO. Yet since it's in the comestibles realm and is following the hugely successful Beyond Meat IPO, it'll probably attract attention on that basis. The company's stock should start trading on Wednesday, May 15.

Avantor

The one May IPO that approaches the size of Lyft's and Uber's is Avantor, a company that specializes in medical and laboratory instruments.

Avantor has a wide selection of products and services. According to its literature, its goods find their way into the "biopharma, healthcare, education & government, and advanced technologies & applied materials" sectors. This covers the globe; the company says its clients are located in more than 180 countries.

The company has been loss making over the past three fiscal years, although its most recent quarterly results show a modest degree of revenue improvement. Avantor says it has several avenues for growth, including further international penetration and new product introductions.

Avantor stands to gross a breathtaking $3.2 billion-plus if its shares sell at the top end of their anticipated price range. Stock from this massive issue will land on the NYSE on Friday, May 17, under the ticker symbol AVTR.