large capacity -- singba, meowcafe.

• available in A4 (9 rings) and A5 (6 rings) sizes.
• i think the full capacity is 50 filler pages, not sure. which means:
  • for A4: store up to 450 photocards (9*50).
  • for A5: store up to 200 photocards (4*50).
• hard cover/case, also comes with a baffle page.
• colors available: white, black, pink and purple.
• plain cover allows to create your own deco.
• singba has a macaron collection available in A4 and A5 size (the A5 looks like a wide version). i believe both are 3 or 4 rings.

120p/240p

• a good beginner-friendly binder!
• various sizes, the most common is 3 pcs per page.
• the pages are a bit fragile but it can store photocards quite well.
• matte cover allows to create your own deco.
• good capacity (240 total double side) and won't bend as much even if full.

beon:D

• available in A4 (9 rings) and A5 (6 rings) sizes
  • they also have an A5 wide size, which is more suitable for 5/6 and 7/8 pocket fillers.
• full capacity: 40-50 filler pages.
  • i'd say 40 is a hard limit already, considering my own collection and the exact same binder. i used to store postcards/irregular size pcs + photocards + fanmades together and it was already filled to the brim. i don't use double-sided pages.
• pvc-free material.
• the matte cover allows to create your own deco.
• beon:D has 3 available covers. 1+2 / 3
• not a hard cover but sturdy enough to store photocards. can't be used with the elastic it comes with or else the pages will bend.
  • i don't know if there's baffle pages available for beon:D.
  • silk ribbon can be used as an alternative for the elastic. it won't force the pages down and can enhance deco. not sturdy though.

collect books

• A6 and A7 sizes.
• most have a full capacity of 40pcs front and back.
• it's difficult to find pvc-free collect books so i'd rather not risk buying them to not damage the photocards.
• for me, there are only two possible scenarios to keep a collection in collect books:
  • first, you don't have much space to keep a collection in general. collect books can be kept in drawers, bags, small desks, etc.
  • second, temporary storing. examples:
    • pocas you keep separated from your main collection because you will sell/trade/ship them later.
    • freebies or fanmades. either that you receive/keep or send.
• a third option for keeping a collect book is merch. for example, stray kids has collect books that are merch but they're still made of pvc. (and this absolutely breaks my heart because the pilot collect book is absolutely gorgeous and has different pages to store even irregular sized photocards;;;;;)

hard cases -- such as composition book, checkered board...

• as far as i know, minkys and lucalab are reference brands who work primarily with hard case binders.
• i found most available only for A5 size.
• they have a personal sizing: R25 and R19, where R25 means a thicker book than R19. which means that R25 can support more filler pages inside than R19. they have a size chart but if you want to know the full capacity for each, R19 goes up to 50 sleeves (200 pcs) while R25 gets 80 sleeves (320 pcs).
• full capacity: check their size chart to find what suits you best!
  • also make sure to check binder owner posts. for example, i found this reddit post about lucalab sizing and the commentors recommend not more than 30 pages in these binders.
• i think it's ideal for bigger collections, like:
  • a full group collector; if it's a 4-member group then you can store everyone in a single page but for 5-member groups and onwards you'd have to separate them.
  • pair-and-onwards collectors; if you collect 2 or more people from the same group and want to keep them together.

macaron binders

• there are many brands that work with the macaron model. so far, singba, minuit and minkys are the most common.
• available in A5, A6 and A7 sizes.
• full capacity: for A5, 20 pages at max. i don't know the hard limits for A6 and A7 sizes.
  • i remember seeing these binders in a large/bigger size, but i can't find it anymore. so i don't know if it was the same size but the owner filled it to the brim with pages or maybe a different brand version (like singba's).
• good for those who have small collections or are separating a full collection. example: only for regular pcs, or for era-only pcs.
• can be decorated on the inside and outside.
• available in many colors. the most common are yellow, pink, white and purple. can also be found in green, blue and black, or have a mixture with white.
• keep a secure collection.