In a Japanese baseball shop, two infield gloves from the same maker may be marked kōshiki and nanshiki. These labels describe the type of baseball each glove is designed for. Kōshiki baseball uses a conventional, leather-covered hardball. In Japan’s organized nanshiki game, players use approved rubber baseballs.
Rubber baseballs come in regulated sizes
Ball maker Nagase Kenko lists the approved M ball for adult and junior high play and the J ball for elementary school play. To someone unfamiliar with the game, a rubber baseball might sound like something you take to the park for a casual hit. In Japan, the association approves equipment and organizes tournaments. “Rubber-ball baseball” gives English-speaking readers a clearer picture of the game than the literal shorthand “soft baseball.”
Judge the design separately from the condition
A hardball glove that has seen several seasons can feel supple, and a rubber-ball model can feel firm. How easily a used glove closes tells you something about its current condition. To identify its intended use, read the manufacturer’s classification, look up the model number, and check any markings on the glove itself.
If your league plays with a conventional hardball, start with models you can verify were designed for hardball. Then look at your position and your league’s equipment rules. In a Japanese listing, “infield” is a useful description once you know which ball the glove was built to field.
Compare the two approved ball sizes
Nagase Kenko lists the M ball at a nominal 72 millimeters in diameter and 138 grams in weight, and the J ball at 69 millimeters and 129 grams. Both specifications allow tolerances. The difference may look small on paper. Think of a player with smaller hands trying to get a grip across the ball, and the reason to pay attention to the age category becomes easier to see.
A rubber ball can have a seam pattern molded into its surface. That detail may make it look familiar to someone who plays hardball, but the surface appearance does not establish how the ball is made. If you are explaining Japanese baseball equipment in a listing, start with the approved category and then describe what the ball or glove looks like.
Within rubber-ball baseball, position still matters
After identifying a glove as rubber-ball equipment, look for the position it was designed for. A fielder who receives a feed at second base has to take the ball out quickly. An outfielder running down a fly ball may be more concerned with reaching it and keeping it in the glove. The choice of ball and the choice of fielding pattern are two different steps.
Imagine two infield gloves with similar finger lengths and web designs. One is listed for hardball and the other for rubber-ball play. The similarities in a photo are useful for comparing shapes, but they cannot settle the intended ball. Once you have verified that two gloves were made for the same type of baseball, comparing the pocket and the way they close becomes much more useful.
Read a used listing in order
Start with the ball category, then the position, then the model number. Confirm the throwing hand as well. “Right-hand throw” means the player throws with the right hand and wears the glove on the left. A Japanese listing that says 右投用 describes the same setup. A glove can meet every other requirement and still be unusable for you if you read the handedness the other way around.
When the model number is visible, compare it with the manufacturer’s material. If you find an official page for another product in the same color and series, use it as a lead for further searching. The useful match is the product you are actually looking at. Keep notes about the condition of the leather separately from the hardball or rubber-ball designation.
Check the ball for the competition you will actually play
Once you know the ball categories, read the equipment section of your own competition’s rules. Different organizers and divisions can publish different requirements. If you played with a rubber ball at school, use that experience as a starting point and check what your next league specifies. Where the rules name a ball, you can compare the wording with the manufacturer’s list of approved products.
Keep rubber-ball baseball separate from softball
For an English-speaking buyer, softball means a separate sport. Japanese equipment catalogs also give softball its own category alongside hardball and rubber-ball baseball. In a translated product title, “rubber-ball baseball glove” preserves the distinction. In the description, explain that the manufacturer sold the model for nanshiki play. That gives a buyer enough context to understand the label without already knowing the Japanese term.
Put the decisions in order
If you are shopping for a league, confirm its ball first. If the glove is for playing catch, think about whom you will play with and which ball you will use. If it is a gift, knowing someone likes baseball will not tell you whether their team plays hardball or rubber-ball. Once you have the ball type, throwing hand, and position, you can compare colors and prices among gloves the player can actually use.
What to do if you see a semi-hardball label
Nagase Kenko’s product list also includes the H ball, approved by Japan’s university semi-hardball federation. It appears separately from the M and J rubber balls. If you encounter jun-kōshiki, check the competition’s rules and the equipment maker’s description. The wording may suggest a midpoint between two familiar categories, but that impression alone cannot tell you which equipment the organizer specifies or what ball the glove maker had in mind.
Work through a listing with missing information
Suppose you can see the wrist patch, the palm, and a photo of the glove closed, but the seller describes it only as a baseball glove. Look first for a model code. Check the maker’s material for the type of ball and the position. Then turn to the palm and hand opening to decide whether the glove’s current shape looks right for you. If you begin with the softness, it is tempting to infer a rubber-ball designation from a well-used hardball glove.
Now consider a listing with a legible code and matching manufacturer information but no photo of the opening. The intended use may be clear while the fit is still an open question. Those are different gaps. One calls for a manufacturer’s description and the other for a photo of the actual glove. Once you understand the ball categories, you can ask the seller to photograph a particular marking rather than asking generally what kind of glove it is.
Older equipment may carry a different ball designation
Nagase Kenko dates the launch of its M ball, which combined the earlier A and B categories, to 2017. Its J ball followed in 2018. If an older team photo or a marking on a ball shows a letter you do not see in a current listing, check when the item was used. The present categories are a useful way to read today’s catalog. The maker’s timeline helps explain why an older ball or a period description may use different wording.