Gillette Fusion Pack of 4 Refill Razor Blade Cartridges

4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures.

A blade is the sharp, cutting portion of a tool, weapon, or machine, specifically designed to puncture, chop, slice, or scrape surfaces or materials. Blades are typically made from materials that are harder than those they are intended to cut. This includes early examples made from flaked stones like flint or obsidian, evolving through the ages into metal forms like copper, bronze, and iron, and culminating in modern versions made from steel or ceramics. Serving as one of humanity's oldest tools, blades continue to have wide-ranging applications, including in combat, cooking, and various other everyday and specialized tasks.

Blades function by concentrating force at the cutting edge. Design variations, such as serrated edges found on bread knives and saws, serve to enhance this force concentration, adapting blades for specific functions and materials. Blades thus hold a significant place both historically and in contemporary society, reflecting an evolution in material technology and utility.

Fusion, or synthesis, is the process of combining two or more distinct entities into a new whole.

Fusion may also refer to:

Gillette is an American brand of safety razors and other personal care products including shaving supplies, owned by the multi-national corporation Procter & Gamble (P&G). Based in Boston, Massachusetts, United States, it was owned by The Gillette Company, a supplier of products under various brands until that company merged into P&G in 2005. The Gillette Company was founded by King C. Gillette in 1901 as a safety razor manufacturer.

Under the leadership of Colman M. Mockler Jr. as CEO from 1975 to 1991, the company was the target of multiple takeover attempts, from Ronald Perelman and Coniston Partners. In January 2005, Procter & Gamble announced plans to merge with the Gillette Company.

The Gillette Company's assets were incorporated into a P&G unit known internally as "Global Gillette". In July 2007, Global Gillette was dissolved and incorporated into Procter & Gamble's other two main divisions, Procter & Gamble Beauty and Procter & Gamble Household Care. Gillette's brands and products were divided between the two accordingly. The Gillette R&D center in Boston, Massachusetts, and the Gillette South Boston Manufacturing Center (known as "Gillette World Shaving Headquarters"), still exist as functional working locations under the Procter & Gamble-owned Gillette brand name. Gillette's subsidiaries Braun and Oral-B, among others, have also been retained by P&G.

A razor is a bladed tool primarily used in the removal of body hair through the act of shaving. Kinds of razors include straight razors, safety razors, disposable razors, and electric razors.

While the razor has been in existence since before the Bronze Age (the oldest razor-like object has been dated to 18,000 BC), the most common types of razors currently used are the safety razor and the electric razor.

Refill may refer to:

• Free refill, a drink that can be filled again, free of charge, after being consumed
• Refill (campaign), British environmental campaign
• "Refill" (song), 2012 song by Elle Varner
• Relapse: Refill, 2009 album by Eminem