Company Information       Product Description     abec7 skateboard bearings 608z ball bearing   d-8mm   D-22mm   B1-7mm *authorized distribution of USBB Bearings       Commonly used for Electric Motors, Remote Control Cars, Fishing Reels, Skateboards, Inline Skates, and much more.  

Shields	Metal shields on each side to protect from dust and other contaminates
Lubrication	Wide temperature range (-50°F to + 300°F)
Noise Testing	Noise tested after lubrication
Noise Level	Passes Noise Vibration Standards V3
Precision Balls	Matched ABMA Grade 10 or better for roundness
Raceways	Finely honed Super Finished for long life and low noise
Quality Level	Meet or exceed ABEC 3/C3 tolerances

    The standard inline skates bearings have the designation "608". The "608" means that the bearings are from the 600 series, with a 8mm inner diameter (the width of the hole, i.e., internal bore). The "6" appears to be for the 6mm difference between the inner and outer radii (from the outside edge to the edge of the hole).   608 bearings are also the standard size for skateboard bearings. Quad skates use either type 608 (8mm internal bore) or type 627 (7mm internal bore). The 608's for quads are the outdoor bearings. If your bearings have letters following the "608" (like "S", "Z", or even "ZZ" or "SS") it is the manufacturer's way of denoting sealed or perhaps double shielded bearings. An "RS" label means shielded but that the shields are removeable (i.e., serviceable bearings). To make sure what they mean you should probably check with the manufacturer, since it can vary from company to company.   A little cross-reference on part numbers for bearings, the 7MM ones are for quality indoor skates, the 8MM ones are used for in-lines, other indoor skates and skateboards   After testing dozens of bearings marketed as ABEC 5 and ABEC 7 that he acquired from local shops, online stores and eBay, Foster says that, although some bearings he tested passed the test, his tests indicate that there are quite a few frauds out there  

Skate Bearings and ABEC Ratings

One of the most important parts on a Rollerskate or Skateboard are the Bearings inside the Wheels. There are two types of Covers on Bearings - Shields and Seals. There are 5 ABEC Ratings - 1, 3, 5, 7 and 9. There are 2 Types of Lube for the Bearings - Oiled, or Greased. Most Wheels take 2 Bearings per Wheel - 8 on a Skateboard or 16 for a Pair of Rollerskates. Features:
Higher quality steel races, better quality and grade balls, and a superior surface finish Single, non-contact, removable rubber shield for easy clearing and less friction High speed nylon ball retainer for greater strength and speed High impact testing These bearings hav been tested against crushing forces of over a ton! That's a spicy ollie! 608 is the standard industrial size spec for bearings used in skates and boards.
Z indicates a shield.
All bearings that will fit your board are 608.

ABEC 3 is an industrial standard for tolerances in the bearing. Higher numbers indicate smaller tolerances and less vibration at high speeds (industrial speeds that are equivalent to a couple hundred miles per hour on your board.

ABEC numbers are basically meaningless for skates and boards. There is more difference in quality between makers than in ABEC 1 and ABEC 7. The lubricant used in the bearing will have more effect on speed than different ABEC ratings. What Is a 608z bearing?   The most common standardized ball bearing size is the 608 series. The 608 series is the original standard ball bearing. In the 608 series, the ball bearing typically consists of optional closures, inner race, outer race, balls, and ball retainer. It is characterized by an 8mm inner diameter (the bore of the ball bearings), a 22mm outer diameter, and a width of 7mm. Most of these ball bearings are manufactured to reflect an ABEC rating which is the industry standard to measure the dimensional and manufacturing tolerances of ball bearings. The ABEC rating is graded in five tiers of 1, 3, 5, 7, and 9 ratings, where the higher the rating, the tighter the tolerances of the bearing. Ball bearings that have a high ABEC system rating are used for high precision applications such as the aerospace industry or surgical equipment, and lower ABEC graded ball bearings are used for more everyday bearing applications. ABEC ratings also reflect the relative prices of ball bearings; the higher the grading, the more expensive the ball bearings. 608 bearings are used in a wide variety of applications including skates and skateboards, electric motors, home appliances, and much more. The speed of the ball bearing has no relation to the ABEC rating. Speed of the ball bearing has a direct relation to lubrication, materials and quality. Materials Used in the 608z Bearing Ball bearings are made of a variety of material types, including ceramic and metal. Ceramic ball bearings are generally recognized as superior because they can dissipate the heat and friction generated inside a ball bearing more easily than a normal metal ball bearing can. For purposes of normal usage however, a 608 ball bearing typically consists of chrome steel balls, both for durability and economic reasons, as a ceramic ball bearing can be quite expensive. Keeping your bearing clean and lubricated will make it work better and last much longer. How a 608z Bearing Functions In a 608 bearing, the bearing balls rotate between two rings – an inner ring and outer ring – and are kept apart by a metallic crown type "H" or a two piece metallic ribbon type "R" cage which are interchangeable in most common applications. The entire unit is sealed with a rubber or metal shield. This shield is helpful in reducing the entry of particulate contaminants into the bearing and also reduces the amount of lubricant leakage. Bearings are usually appended with letters like S, Z, SS, or ZZ to indicate that they are sealed, shielded, or double shielded bearings. In fact, just by looking at the part number of a 608 ball bearing, you can tell what type it is. 608 ball bearings from NMB Tech are pre-lubricated either with oil or grease to make them less susceptible to corrosion or bearing failure, and to allow them to withstand high temperatures. . Packaging & Shipping     LOGISTICS     Factory show     THE TEAM     EXHIBITION CUSTOMERS     FAQ welcome your any bearing's inquiry, We must be helpfully for you!!! pls contact us.