This week, 4 Communications Equipment stocks are worse, according to the Portfolio Graderdatabase. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Bel Fuse Inc. Class B’s (BELFB) rating weakens this week, dropping to a D versus last week’s C. Bel Fuse Inc. Class B designs, manufactures, and sells products used in networking, telecommunications, high-speed data transmission, and consumer electronics. The company also gets F’s in earnings revisions and earnings surprise. For more information, get Portfolio Grader’s complete analysis of BELFB stock.

Alliance Fiber Optic Products, Inc. (AFOP) earns a D this week, moving down from last week’s grade of C. Alliance Fiber Optic Products, Inc. engages in the design, manufacture, and marketing of a range of fiber optic components and integrated modules incorporating these components to communications equipment manufacturers and service providers in North America, Europe, and Asia. The company also gets F’s in earnings surprise. For more information, get Portfolio Grader’s complete analysis of AFOP stock.

Polycom, Inc. (PLCM) is having a tough week. The company’s rating falls from a C to a D. Polycom, Inc. develops, manufactures, and markets a line of video, voice, data and web conferencing collaboration solutions. The company also gets F’s in earnings momentum. For more information, get Portfolio Grader’s complete analysis of PLCM stock.

Inventergy Global Inc (INVT) experiences a ratings drop this week, going from last week’s C to a D. The company also gets F’s in sales growth, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of INVT stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.