Replacements may be frequently needed - Crosman Hand Stop Swivel

Regarding the Crosman Hand Stop Swivel:
This product has a manufacturing flaw that causes the small ball bearings to fall out after some use, thus rendering the detachable swivel useless. Frequent replacements may be required. Unfortunately, because of its unique application (specifically for Crosman air rifles), it's difficult to find a suitable alternative or aftermarket part to replace it. ***

Regarding Optics Planet.com:
Hats off to Optics Planet.com for their customer service efforts. At first, we had a hard time tracking down the correct point of contact to order the part, then they shipped the wrong part, but when we notified them of the error, they were quick to fix the problem, and even exceeded our expectations by working with us on a customized delivery schedule. ****