The Dycem 'Black Hole' rubbercello end-pin stop/mat. It is much blacker in real life than it looks in the pictures.
Dycem STN1130 "Hole" Non Slip Cello Mat - Black
Cello Anti-slip Mat, Cello Mat Portable Non Slip Cello Endpin Rest Holder with Metal Eye Instrument Accessory (Brown)
Cheerock Non-slip Cello Endpin Anchor Stopper Rest Holder Stand Anti-slip Device for Cello Adjustable Cello Endpin Strap with Thickened Foam Pad, Great for Cellist Practice Performance
Cabilock Anti-slip Cello Bottom Protector Mat with Rubber PVC Material Non-slip Cello Spike Holder for Floor Protection Compact and Portable Musical Instrument Accessory for Practice and
Cello Stopper Rest Pad, Non-Slip Cello Endpin Holder Cello Rest Pad Soft Floor Protector Instrument Accessory(#A) Violin Accessories
