1、The package includes: including 8 replacement suction cups, in 2 versions (4pcs crosshole suction cups and 4 ring suction cups each), which is enough to meet your needs and can also be shared with family and friends who have cats. 2、Applicable Surface: Cat bed suction cups can be applied to sleek surfaces, such as tiles, glass, etc., with strong suction power, which can support your cat window bed well. 3、PVC Material: Cat bed suction cups are made of premium PVC plastic, sleek surface, safe and strong, easy to stick to wall and windows, no residue, long use time. 4、Widely Used: Cat bed suction cups are suitable for hanging ropes, wire, plastic rods and chains. It can also be applied to hanging cat window hammocks, cat window perching, cat window seats, cat window beds, etc. 5、Different Diameters: The cat window bed suction cup is available in diameters of 8cm/3.15in and 8.5cm/3.35in, which can be selected according to actual needs to help fix the cat's hammock.