This week, 5 Commercial Services & Supplies stocks are improving their overall ratings on Portfolio Grader. Each of these stocks is rated an “A” (“strong buy”) or “B” overall (“buy”).

This week, Cintas Corporation’s (CTAS) ratings are up from a B last week to a A. Cintas Corporation provides uniforms first aid items, and other products to businesses. The company also gets A’s in return on equity. For more information, get Portfolio Grader’s complete analysis of CTAS stock.

Tetra Tech, Inc. (TTEK) shows solid improvement this week. The company’s rating rises from a B to a A. Tetra Tech, Inc. is a global consulting and engineering company that serves public and private clients by addressing needs for water, environmental services and renewable energy. The company also gets A’s in earnings momentum. For more information, get Portfolio Grader’s complete analysis of TTEK stock.

Heritage-Crystal Clean, Inc.’s (HCCI) ratings are looking better this week, moving up to a B from last week’s C. Heritage-Crystal Clean, Inc. offers parts cleaning services. The company also gets A’s in earnings revisions and earnings surprise. For more information, get Portfolio Grader’s complete analysis of HCCI stock.

CompX International Inc. Class A (CIX) earns a B this week, jumping up from last week’s grade of C. CompX International Inc. Class A manufactures security products, precision ball bearing slides, and ergonomic computer support systems that are used in the office furniture, transportation, postal, tool storage, appliance, and related industries. For more information, get Portfolio Grader’s complete analysis of CIX stock.

Casella Waste Systems, Inc. Class A (CWST) boosts its rating from a B to a A this week. Casella Waste Systems, Inc. Class A provides resource management expertise and services related to solid waste collection, transfer, disposal, and recycling to residential, commercial, municipal, and industrial customers. The company also gets A’s in earnings growth and earnings surprise. For more information, get Portfolio Grader’s complete analysis of CWST 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.