Stamped with "BR (M)". It's 4.5" tall and 3.75" wide, weighing about 1lb (430g).
Vintage Heavy Duty Screw Jack House Barn Railroad Jack Ratcheting Screw Jack 
Vintage Heavy duty British Railway cast iron bracket HWD 1952 BR
Vintage Heavy-Duty Railway Sleeper Anchor Bolts (Set of 3) British Rail Track
Vintage Fleischmann 705 Model Railway Transformer | 14V AC 50VA | Heavy Duty
Vintage SIMPLEX No. 4 Screw Jack. Heavy Duty..
