To provide a pet cage and a connected pet cage having high expandability and a connecting part set.SOLUTION: This tray 1 is provided with a tray 1 having a bottom portion, a peripheral wall portion provided at a peripheral portion on the upper surface side of the bottom portion, and a peripheral end portion 15 which is a peripheral portion and is provided outside the peripheral wall portion And a cage body disposed on the peripheral end portion. The cage body includes a right side panel 37 disposed on the first peripheral end portion of the peripheral end portion 15 and a second peripheral surface portion which is located on a second peripheral surface of the peripheral end portion 15 facing in a different direction from the first peripheral end portion And a rear panel 33 disposed on the end portion. The rear panel 33 is a wire panel in which a plurality of wire rods 331 are combined in a lattice pattern. When the distance between the right side panel and the side surface 15 c of the first peripheral end portion is L 1 and the distance between the adjacent wire materials among the plurality of wire members 331 of the rear panel 33 is L 2, L 1 2 L 2 .(FIG.【課題】拡張性が高いペット用ケージ及びペット用連結ケージと、連結部品セットを提供する。【解決手段】底部と、底部の上面側の周辺部に設けられた周壁部と、周辺部であって周壁部よりも外側に設けられた周端部15とを有するトレー1と、トレー1の周端部上に配置されるケージ本体とを備える。ケージ本体は、周端部15のうち第1の周端部上に配置される右側面パネル37と、周端部15のうち第1の周端部とは異なる方向に面する第2の周端部上に配置される後面パネル33と、を有する。後面パネル33は複数本の線材331を格子状に組み合わせた線材パネルである。右側面パネルと第1の周端部の側面15cとの間の距離をL1とし、後面パネル33の複数本の線材331のうち隣り合う線材間の距離をL2としたとき、L1×2≦L2である。【選択図】図7
